Donald Trump’s rise to the top of the GOP ticket is resetting the Senate and House race landscape, emboldening Democrats and putting Republicans on the defensive as they brace for running alongside the most unpopular presidential nominee in recent history.  

Both parties had spent months preparing for a potential Trump nomination, but the suddenness of Ted Cruz’s exit from the presidential primary sent shock waves through each. In an era where down-ballot races are increasingly shaped by the national political climate, Trump’s presence could change what races are competitive and how both parties run their campaigns.  

Signs of the shifting paradigm were evident Wednesday, less than 24 hours after Trump’s victory in Indiana. Democrats were celebratory, issuing statements mocking the GOP as the “party of Trump” while privately predicting which new states and districts were now in play.  

“Here are the five words that are striking fear into Senator Rob Portman: presumptive Republican nominee Donald Trump,” David Bergstein, spokesman for Ted Strickland’s Senate campaign in Ohio, said in a statement issued shortly after Trump’s win. In Democrats’ view, an election year already shaping up favorably is now poised to turn into a wave that could sweep them to big gains in the Senate and House.  

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Republican campaigns, meanwhile, tried steadfastly to ignore Trump’s victory. While the Strickland campaign highlighted Trump, for instance, Portman’s operatives issued a news release Wednesday attacking the former governor for cutting education funding. The Ohio race is one considered a tossup/tilt Republican by the Rothenberg & Gonzales Report.  

Privately, many of the operatives running the party’s House and Senate campaigns acknowledged the tough task ahead.  

When asked what’s next for his campaign, one GOP Senate operative replied “going to the mattresses,” a reference to a mafia term used in “The Godfather” for going to war.  

The flurry of action was tied to a candidate whose poll numbers are so low that Republicans worry he’ll drag down the rest of the ticket. A survey released Wednesday from CNN/ORC found that likely Democratic nominee Hillary Clinton led Trump 54 percent to 41 percent. Among only women, her edge swelled to 26 points.  

“Normally there are coattails with a nominee,” said Ron Bonjean, a Republican strategist. “But with Trump and his high negatives, that can have a ripple affect across Senate and House races with members who feel they are at risk.”  

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To be sure, strategists from both parties are still scrambling to assess Trump’s impact on the race. To some Republicans, the potential fallout is either unclear or overstated. And even Democrats concede that any thought they’ll take the House majority is, at best, premature.  

Republicans hold 54 seats in the Senate, meaning that if the party does not regain control of the White House, they can afford to lose a net of only three seats to hold their majority. Their hold on the House is much firmer: The GOP would need to lose a net of 30 seats there to cede control to Democrats.  

Democrats are hoping Trump will help them capture some of those seats. “This is trouble for House Republicans across the map, but particularly damaging in suburban districts, those with high number of Latinos, African-Americans, and young people,” said New Mexico Rep. Ben Ray Lujan, chairman of the Democratic Congressional Campaign Committee  

According to the man in charge of the House GOP’s political arm, Republicans are in no danger of losing the chamber even with Trump. The seats they would need to win are simply too Republican-leaning and well-defended by GOP incumbents and challengers.  

“I would love to see the list that gets you below 218,” Walden said in an interview last week. “That’s 30 seats that you have to flip, and I don’t see that.”  

Democrats don’t dispute that the House, where many seats were drawn favorably for the GOP during the last round of redistricting, isn’t yet in play. One aide to the Democratic Congressional Campaign Committee said that it’s too early to know if the party can retake a majority.  

The aide added that the party’s challenge in House races is different than it is in many states, where Democratic candidates can focus on driving up turnout in urban areas. Many battleground House districts don’t include urban areas, making an anti-Trump strategy more difficult to implement.  

“Between now and Election Day, we have to find persuadable voters, in particular those who are turned off by Trump,” said the aide. “We have to figure out why they’re turned off by Trump. And take [the] last step, to make sure they’re also turned off by House Republicans.”  

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Senate Democrats are already working to pick up seats in Illinois, Wisconsin, Ohio, Pennsylvania, New Hampshire and Florida — states that President Barack Obama won twice. Now they have their sights set on a handful of GOP-controlled states once regarded as second-tier opportunities. Their list includes Sens. Roy Blunt in Missouri, Richard Burr in North Carolina and John McCain in Arizona.  

In addition to a bump from Trump, officials with the Democratic Senatorial Campaign Committee say they’ve recruited strong candidates in these states to put them in play, like finding former Army intelligence officer Jason Kander to run against Blunt in Missouri. Kander raised more money than Blunt in the first fundraising quarter of the year.  

Those candidates and a tough environment will “force Republicans to play defense in many more seats than they were hoping or anticipating dealing with this year,” said Sadie Weiner, spokeswoman for the DSCC.  

Republicans fire back that Democrats have their own unpopular standard-bearer to worry about.  

“There is a reason Democrats aren’t lining up to campaign with Hillary Clinton,” said Andrea Bozek, spokeswoman for the National Republican Senatorial Committee. “She is a toxic candidate whose failed leadership has put the security of our country at risk.”  

She added that “Republicans will maintain control of the Senate because we have better-prepared candidates running better, more coherent, and more thoughtful campaigns.”  

Contact Roarty at alexroarty@cqrollcall.com and follow him on Twitter @Alex_Roarty.

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