Thanks mostly to Donald Trump, American politics is more in flux than it has been since the Solid South abandoned the Democratic Party in the wake of the civil rights revolution.

The Republican Party — once in thrall to groups like the Moral Majority and the Christian Coalition — has nominated a thrice-married former reality-show host whose grasp of the Bible needs to be graded on a curve. During Monday night's debate, Trump again repudiated such bedrock GOP principles as free trade and fidelity to NATO.

Hillary Clinton, blessed with the support of large segments of the moderate Republican foreign policy establishment, may be the most hawkish Democratic presidential nominee since Hubert Humphrey in 1968. Though, in fairness, the Al Gore of 2000 probably comes close.

The political map is in the midst of its biggest rewrite since 1996 when Bill Clinton swept such now safe GOP bastions as Louisiana, Arkansas, Missouri, Kentucky, Tennessee and West Virginia. It is weird when the 2016 action pivots around Pennsylvania (which last was carried by the Republicans in 1988) and North Carolina (which has only gone Democratic once in the last nine elections).

That's why traditionalists, regardless of party or ideology, should have been thrilled when Hillary during the debate emphasized a Democratic theme older than even FDR's theme song, "Happy Days Are Here Again." In a topsy-turvy political world, there is only one constant — the Democrats will always denounce Republican "trickle-down economics."

Clinton gussied it up a bit, calling it "trumped-up trickle-down," in an obviously rehearsed line that she repeated twice for emphasis. As the former New York senator put it: "Trickle-down did not work. It got us into the mess we were in, in 2008 and 2009. Slashing taxes on the wealthy hasn’t worked."

The expression — "trickle-down economics" — sounds like it was lifted from another era. You can almost see a farm family at supper spilling a pitcher of milk and their cat lapping it up from the floor.

William Safire, the late New York Times columnist and legendary political linguist, traced the concept back to populist William Jennings Bryan's "Cross of Gold" speech" that electrified the 1896 Democratic convention. Bryan denounced conservatives who believed that if "you legislate to make the well-to-do prosperous, their prosperity will leak through on those below."

But it took another great Democratic orator, Franklin D. Roosevelt, to get the wording right. In an October 1932 campaign address in Detroit, in the depth of the Depression, Roosevelt ridiculed those who believe that "if we make the rich richer, somehow they will let part of their prosperity trickle down on the rest of us."

Just because FDR said it doesn't mean that a line will endure as a staple of Democratic oratory for eight decades. You don't hear Democrats today — especially not Hillary Clinton — denounce the "economic royalists" whom Roosevelt excoriated in his 1936 re-election campaign.

But somehow "trickle-down" dripped its way onto the texts of Democratic Party speechwriters. Part of its appeal was the homeyness of the imagery and part of it was its often apt description of GOP economic proposals.

Campaigning on behalf of the Democratic ticket in October 1952, Harry Truman lamented that during the 1920s "many short-sighted people honestly believed that, if big business got along well, enough wealth and income would trickle down to the rest of the population to keep the system going."

The expression might have died out during the Kennedy years when the mantra was "a rising tide lifts all boats." But first Richard Nixon and then, especially, Ronald Reagan brought "trickle-down" back into the Democratic lexicon.

Probably the architect of the revival of "trickle-down" was David Stockman, Reagan's first OMB director. In an exceptionally candid series of 1981 interviews with Bill Greider for the Atlantic Monthly, Stockman confessed that the unrealistic budget estimates of "supply side" economics were needed to pass Reagan's tax cuts.

As Stockman memorably put it, "It's kind of hard to sell 'trickle-down' so the supply side formula was the only way to get tax policy that was really 'trickle-down.'"

Bill Clinton's 1992 presidential campaign — which was shaped as the belated Democratic response to Reaganism — regularly attacked "trickle-down economics." In his first debate with George H.W. Bush and Ross Perot, the Arkansas governor argued that the Reagan tax cuts failed to "trickle down" to the middle class.

In fact, during that 1992 campaign, Hillary Clinton joined in the "trickle-down" chorus. Campaigning on her own in Florida in late August, Hillary told a crowd of mostly women at the Tampa Convention Center that trickle-down economics hadn't worked under either Reagan or Bush.

At the beginning of her current race for the White House, Hillary harked back to Reagan in her first major economic speech in July 2015. "For 35 years," she said, "Republicans have argued that if we give more wealth to those at [the] top by cutting their taxes … it will trickle down to everyone else. Yet every time they have a chance to try that approach, it explodes the national debt, concentrates wealth even more and does practically nothing to help hard-working Americans."

Even though "trickle-down" didn't make it into Clinton's acceptance speech in Philadelphia, she brought it back to center stage Monday night. It was just another moment in the spotlight for the unsinkable epithet that Democrats have used to denounce Herbert Hoover, Ronald Reagan and now Donald Trump.

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It’s hard to pick the worst moment for Donald Trump on a night during which he flailed trying to find balance. But an early gaffe largely lost in the cross-talk indicated that he was more easily baited, and thirstier for blood, than he was prepared for a presidential debate.

And it smacked of a mistake that helped cost Gerald Ford a return engagement as president in 1976.

“You’re telling the enemy everything you want to do,” Trump said in a familiar criticism of Clinton’s plan for dealing with the Islamic State. Then he deviated: “No wonder you’ve been fighting — no wonder you’ve been fighting ISIS your entire adult life.”

Back in 1976, Ford said “there is no Soviet domination of Eastern Europe,” which, of course there was. Trump placed the birth of ISIS in 1965, about six decades too early.

It’s not that Trump really thinks ISIS formed when Clinton was 18, or that she’s only been an adult for the last several years. But Clinton was under his skin, and he reacted like a child by simply blurting out the first attack that came to mind.

[Five Objectives for Hillary Clinton in the Debates]

Clinton called for fact-checkers to take a look at that one as the candidates and moderator Lester Holt grappled for control of the debate. In any normal year, such a wild claim might be disqualifying — it displayed a lack of knowledge of ISIS far worse than Rick Perry’s inability to name a Cabinet department on command. But in a year when facts don’t seem to matter, the truth was far less important than what the response said about Trump’s temperament.

He couldn’t keep his cool in a pressure-packed moment. Clinton had just countered a Trump attack on her ISIS proposal by taunting him. “At least I have a plan,” she said.

Then, Trump lost his composure. In doing so, he underscored the marquee phrase of her Democratic convention speech, when she said “a man you can bait with a Tweet is not a man we can trust with nuclear weapons.”

After that, Trump never recovered for long. And that must have been very frustrating for his fans — especially after he effectively crushed Clinton on trade in the debate’s opening moments.

But the ISIS exchange set the table for Clinton to calmly prosecute her case against Trump on taxes, foreign policy and criminal justice. She was so much better on substance that Trump quietly agreed with her at least three times.

[Hillary's Honesty and Trump's Temperament]

Holt countered Trump when he lied about his pre-war support for the Iraq invasion and his role in promoting what Clinton called the “racist birther lie.”

Trump and his spinners can insist he won, but they know in their hearts that Clinton, who wasn’t even at her best, wiped the floor with him. Trump’s ISIS gaffe was that of a bush-leaguer stepping to the plate at Yankee Stadium and buckling at the sight of his first big-league curve.

Indeed, Clinton’s missteps might have stood out more against a more seasoned debater who was positioned to take advantage of them rather than turning focus back on his own shortcomings. But in the end, Trump lied, denied and bullied his way to the worst debate performance since the advent of television.

Roll Call columnist Jonathan Allen is co-author of the New York Times-bestselling Clinton biography “HRC” and has covered Congress, the White House and elections over the past 15 years.

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To hear Donald Trump tell it for the last year, Senate Republicans were weak, dumb losers, and not just the ones he ran against for president. He infamously called Sen. John McCain “not a war hero” and tweeted that Sen. Jeff Flake was “a very weak and ineffective senator … Sad!” He lambasted Sen. Mark Kirk as “dishonest” and a “loser,” and told an Atlanta rally that he wished Republican leaders in Washington would “just please be quiet” so he could win the race by himself.

He tagged Sen. Lindsey Graham “a disgrace” and “one of the dumbest human beings I have ever seen.” Sen. “Little Marco” Rubio was “just another Washington, D.C., politician” with “the biggest ears I’ve ever seen.” Sen. Rand Paul was “truly weird” and Sen. “Lyin'” Ted Cruz was not only dishonest, but by Trump’s suggestion, his father was involved in the Kennedy assassination.

So imagine the irony if those useless slobs in the upper chamber, 22 of whom will share the ballot with Trump in November, actually help him win the White House on Election Day. That emerging possibility is a reversal from the assumption leading up to this point in the cycle, which said that Trump’s coattails would determine the fates of Senate Republicans, and not the other way around. If Trump did well, the thinking went, they would do well. If he tanked, he would take them down with him like passengers on the Titanic.

But as Trump’s poll numbers tumbled through the summer, the Republicans running for re-election worked to build their own brands, with their own paths to victory, independent of their erratic nominee. The result is now a class of Republican Senate candidates who are nearly all more popular than Trump, with many who have built robust campaign operations of their own, above and beyond Trump’s scattershot approach to Election Day.

[The Down-Ballot Shuffle, a Ticket-Splitting Revival]

An analysis last week by The Washington Post showed Senate Republican candidates overperforming Trump by an average of 4 points in competitive states. Only Sen. Ron Johnson in Wisconsin and Rep. Todd Young in Indiana are polling worse than Trump.

In critical swing states like Arizona and Florida, “Not a War Hero” McCain and “the Biggest Ears I’ve Ever Seen” Rubio are not only pulling ahead of their Democratic rivals, they’re also outpolling Trump by double digits. So is Rob Portman in Ohio, where Portman has built a massive turnout operation to get his own voters to the polls, no matter what the Trump campaign does or does not do on Election Day. Ohio is now tied for Trump and Clinton, but a major Portman victory could deliver just enough persuadable voters to the polls to give Trump a margin of victory.

In Georgia and Utah, two states that should be easy wins for Trump but are dangerously close contests instead, Sens. Johnny Isakson and Mike Lee are way out ahead of their rivals. If Trump wins those states, he may have them to thank for bringing Republicans to the polls who might not have bothered otherwise.

So how would a Trump White House work with a Republican Senate if the party defied expectations and won them both? It’s hard to imagine President Trump being able to bury the hatchet with senators he maligned along the way, who could then chair committees, allocate funds, and hold the votes for whatever agenda Trump has in mind. They might not forgive him for the things he said, and he might not forgive them for some insults they hurled in the heat of the campaign.

[Senate Republicans Leave Trump Meeting With Little to Say]

After months of being called “Little Marco,” Rubio snapped and called Trump a small handed, orange-hued “con artist.” Sen. Ben Sasse described Trump as one half of “the dumpster fire” that the election has become. Mike Lee said Trump “scares me to death,” while Ted Cruz, after the Your-Father-Helped-Kill-Kennedy bit, called Trump a “sniveling coward” and “a narcissist the likes of which I don’t think this country has ever seen.”

But it’s possible that all of those insults and nasty words about Trump during the primary were just politics masquerading as conviction.

On Friday, Ted Cruz endorsed Trump after declaring at the Republican convention that he was “not in the habit of supporting people who attack my wife and father.” But Cruz apparently is in the habit of supporting people who could be in power in the near future.

Even if Republican senators hold their own, the question remains whether voters who come out for their senators will also vote for Trump, split their ticket or skip the top line altogether. Ticket-splitting reached a 92-year low in the 2012 elections, but as Walter Shapiro pointed out here this summer, ticket splitting may not be dead, it might just be sleeping. The 2016 election will answer that question once and for all.

Roll Call columnist Patricia Murphy covers national politics for The Daily Beast. Previously, she was the Capitol Hill bureau chief for Politics Daily and founder and editor of Citizen Jane Politics. Follow her on Twitter @1PatriciaMurphy.

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"I also have a much better temperament than she does." — Donald Trump

In 1973, a trash-talking, over-age self-described "chauvinist pig" named Bobby Riggs took on Billie Jean King in a tennis match in the Houston Astrodome that was billed as The Battle of the Sexes. King won in straight sets.

History repeated itself Monday in the first one-on-one debate of Donald Trump's career.

After controlling himself for the first two questions, Trump discarded all the advice that he must have received from debate handlers like Roger Ailes. Drinking water nervously and grimacing when he wasn't speaking, Trump began interrupting Hillary Clinton after almost every sentence.

While Trump's shouted comments initially landed glancing blows (attacking Bill Clinton over NAFTA), the former reality-show host soon degenerated into pure gibberish. In the history of presidential debates, it is hard to top Trump's non sequitur, "No wonder you've been fighting ISIS all your life."

[Another Way Trump Could Flunk the Electoral College]

In a 2000 Senate debate, Rick Lazio angrily walked over to Hillary Clinton's lectern and demanded that she sign a pledge. The Lazio gambit was criticized afterwards as re-enacting the kind of menacing moments that women fear. But compared to Trump, Lazio took etiquette lessons from Emily Post.

During it all, moderator Lester Holt played Caspar Milquetoast, a 1920s cartoon figure who personified soft-spoken timidity. In fact, it is safe to say that Holt gave potted plants a bad name.

In the debate, Trump boasted again that he wanted to keep his plans for taking on ISIS a secret to maintain strategic advantage. But what was fascinating was that Trump's debate strategy offered no surprises. It was a greatest hits tour of Trump's rudest moments, devoid of even flashes of humor.

By playing to type, Trump played right into Clinton's well-executed game plan. If there was a moment when Hillary sensed that it was going to be her night, it probably came when she baited Trump for the first time. In a riff on trickle-down economics, Clinton said that her opponent "started his business with $14 million borrowed from his father."

It was a mild dig — and a more disciplined candidate might have ignored it. Instead, Trump began his answer on jobs by saying defensively, "Before we start on that — my father gave me a very small loan in 1975, and I built it into a company that's worth many, many billions of dollars."

[Trump-Clinton Debate: Much Ado but Little Impact?]

By the way, the bilious billionaire's answer on bringing back manufacturing jobs was a Trumpian tautology: "The first thing you do is don't let the jobs leave."

Even when Clinton handed him opportunities, Trump failed to seize the moment. In the midst of answer about enforcing the terms of trade deals, Hillary suddenly said, "I'm going to have a special prosecutor." Now if there are two words that no Clinton should ever utter in a debate, they are "special prosecutor." But, for the only time Monday night, Trump stayed silent.

Trump came across as the least prepared prime-time debater since the 1976 vice presidential face-off when Bob Dole slouched against the lectern and railed against "Democrat wars in this century."

Violating every protocol of everyman politics, Trump actually bragged about not paying any taxes: "That makes me smart." And unlike any prior candidate running for the commander in chief, Trump freely admitted that until recently, "I haven't given lots of thought to NATO."

History suggests that voters generally score debates more on presentation than on policy. But on both fronts, Clinton was at the top of her game, smiling frequently and naturally. If authenticity can be a learned skill, then the former secretary of state learned it for this debate.

As Tim Crouse recounted in "The Boys on the Bus," his classic account of the press covering the 1972 campaign, reporters used to hover over the typewriter of Walter Mears, the AP correspondent, wanting to know what the news lead would be. That form of pack journalism now seems quaint, but even in an era of social media it takes a few days for the after-effects of a debate to percolate through the system.

[Poll: Clinton, Trump Tied as First Debate Arrives]

That is why it is a risky game to predict where the polls will be at the end of the week. But it is hard to imagine that there was a single moment in the debate that would have convinced a wavering college-educated woman in the Philadelphia or Cincinnati suburbs to vote for Trump. In fact, Trump seemed to be debating with the single-minded goal of turning his gender gap into a canyon.

Forty-three years after the first Battle of the Sexes, Hillary Clinton defeated Donald Trump in straight sets.

Roll Call columnist Walter Shapiro is a veteran of Politics Daily, USA Today, Time, Newsweek and the Washington Post. His book on his con-man great-uncle was just published: "Hustling Hitler: The Jewish Vaudevillian Who Fooled the Fuhrer." Follow him on Twitter @MrWalterShapiro.

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For anyone following gun control (or gun safety) as political issue, it would be easy to dismiss 2016 as just another year where a whole lot happened, but nothing changed.

There have been 224 mass shootings in the United States so far this year, including the massacre at the Pulse nightclub in Orlando and the July attack on Dallas police officers. After every major incident, Washington followed the now-familiar script of outrage, calls from Democrats for gun restrictions, denial from Republicans that guns are the problem, and then, as usual, gridlock.

But as Election Day gets closer, an incremental, but important shift has modified gun safety as a usually partisan campaign issue. A handful of Republicans in must-win Senate seats are now running on their willingness to embrace even modest gun reforms, while outside interest groups are crossing the aisle to reward those Republicans for doing it.

The highest profile Republican who may be changing the rules on guns is Republican Sen. Patrick J. Toomey, who is locked in a dead-heat race in Pennsylvania against Katie McGinty. Toomey blazed into the Senate in 2008 as an unapologetic conservative and former president of the Club for Growth with an A rating from the National Rifle Association. So it was striking when he joined Sen. Joe Manchin, D-W.Va., after the shootings at Sandy Hook Elementary School to sponsor legislation to expand background checks for firearms purchases.

Toomey joined Democrats this year on a similar bill after the San Bernadino shootings and voted over the summer to cross check gun purchases against the terror watch list.

The Washington politics on guns may be complicated for Toomey, but attitudes on the issue at home in Pennsylvania are unambiguous. A PPP poll of the state in August showed 85 percent of all voters in the state in favor of background checks on all gun purchases, including 80 percent of Republicans.

[Gun Control Meets Congressional Dysfunction]

The issue is usually a potent partisan issue for Democrats, who typically portray Republicans as puppets of the gun lobby, but Toomey's decision to sponsor and vote for gun restrictions has made that almost impossible for Katie McGinty, especially after PACs led by Gabby Giffords and former New York Mayor Michael Bloomberg endorsed Toomey in recent weeks.

The Bloomberg PAC, Independence USA, is running nearly $750,000 of ads in the Philadelphia suburbs, where he has to perform well to win reelection. An especially powerful ad features the daughter of Sandy Hook Elementary's principal, who was killed protecting children at her school.

“Pat Toomey crossed party lines to do the right thing," she says.

[Democrats 'Not Worried' About Punishment for House Sit-In, Hoyer Says]

In an op-ed for CNN, Giffords and her husband Mark Kelly praised both Toomey and Illinois Republican Sen. Mark Kirk as principled on the issue that nearly cost her her life when she was shot by a constituent at a town hall meeting.

The endorsement came at a pivotal time for Kirk, who has trailed behind Democratic Rep. Tammy Duckworth and must have support from cross-over Democrats in the state, which is even more in favor of tougher gun laws than the rest of the country. Kirk has long been on the outs with the NRA. More important for Kirk is Gifford's praise as an independent pragmatist, the brand Kirk has been working to push.

[Gun Compromise Faces Challenges From Right and Left]

In all-important Florida, guns have become a crucial issue in that state's Senate race. Sen. Marco Rubio said the Pulse night club shooting so moved him that he decided to run for another term.

Last week, Eric Garcia reported that Rubio introduced legislation to notify the FBI if the subject of a federal terrorism investigation in the last 10 year tries to buy a gun. Rubio's opponent, Rep. Patrick Murphy, dismissed the bill as Rubio's effort "paper over" a weak record, but it's astonishing, nonetheless, to see a conservative Republican introduce a gun bill less than two months before Election Day.

In 1994, the assault weapons ban was blamed as the reason dozens of Democrats lost their seats. In 2016, a similar decision by Republicans may be the reason some Republicans keep their jobs. If that's the result, 2016 will end up being the year the politics of guns changed, no matter what legislation ended up passing on Capitol Hill.

Roll Call columnist Patricia Murphy covers national politics for The Daily Beast. Previously, she was the Capitol Hill bureau chief for Politics Daily and founder and editor of Citizen Jane Politics. Follow her on Twitter @1PatriciaMurphy.

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