It’s the not-so-secret secret about serving in Congress: No members attend all the hearings for the committees on which they serve.

But every two years, Republicans and Democrats suspend that common knowledge and attack incumbents for poor committee attendance.

Senators miss a lot of hearings and briefings, often for legitimate reasons, like attending another hearing that’s happening at the same time. But in a political world driven by optics, the legitimacy of these attacks isn’t what matters.

Just because it may be a bogus attack doesn’t mean it doesn’t work. After prevalent use in 2014, it’s back this year in at least six competitive Senate races.

The latest instance is from Indiana, where former two-term Democratic Sen. Evan Bayh wants his old job back.

Bayh missed 92 percent of hearings held by the Special Committee on Aging during his 12 years in the Senate, ending in 2010, according to a Republican review of hearing transcripts. And he attended no hearings for the committee during the last five years he was in Senate, according to GOP operatives who reviewed official committee transcripts.

Allies of Rep. Todd Young, Bayh's Republican challenger, plan to use those statistics “to very aggressively highlight Bayh's own record and hypocrisy on Social Security and Medicare,” according to one Republican with knowledge of the race, who was granted anonymity to discuss not-yet-apparent campaign tactics.

Bayh’s Aging panel attendance record may sound egregious.

But the context voters likely won’t hear in any forthcoming advertising is that there are three levels of committees in the Senate based on importance. This particular committee is a B-level committee, and it doesn’t have legislative authority. It can submit recommendations for legislation to the Senate, and it has conducted oversight of Social Security.

At the time Bayh left the Senate, he served on four A-level committees, including Armed Services, Banking, Energy and Natural Resources, and Intelligence. Bayh’s campaign points out that for 21 of about 85 Aging Committee hearings the senator missed during the last five years of his tenure, he was attending Banking, Armed Services or Intelligence hearings.

“It's pretty rich for Congressman Young to attack Evan Bayh for doing his job by attending classified intelligence and armed services hearings, or focusing on the economy two days after Lehman Brothers fell, when he has been silent in the majority of his Armed Services hearings — when he bothers to show up,” Bayh campaign spokesman Ben Ray said.

Young served on the Armed Services committee during his first term in the House, from 2011 to 2012.

Since missed hearings are a daily occurrence on the Hill, there’s no shortage of these attacks. For every punch one campaign throws, the opposing campaign can often come up with an attack on their opponent’s attendance at a different committee. But they are not always comparing apples to apples.

[Why Senate Attendance Attacks Are Usually Bogus]

For starters, House and Senate committees treat attendance differently in the public record. Senate Aging employs a clerk to record attendance. But on House Armed Services, no attendance is taken. The only way to ascertain whether a lawmaker showed up is to search the transcript for a verbal comment or screen video footage.

Democrats concluded that Young was silent on Armed Services by reviewing committee transcripts. But just because Young, a junior member, didn’t ask a question, it doesn’t mean he wasn’t there. He also could have submitted a written question.

Indiana is hardly the only place where absenteeism attacks have come up. Republicans effectively used them against North Carolina Sen. Kay Hagan and Iowa Rep. Bruce Braley, among others, in 2014.

But this year, Democrats are on offense and they’ve been launching similar attacks on Republicans — some in paid media, and some just in earned media.

Just last week, Kentucky Sen. Rand Paul’s Democratic opponent, Lexington Mayor Jim Gray, accused Paul in a press release of being “AWOL from his Senate responsibilities” since the Senate returned from its summer recess because he had missed committee hearings.

The day before, the Pennsylvania Democratic Party had this to say about GOP Sen. Patrick J. Toomey showing up at Banking Committee hearing on Iran: “No, it wasn’t a unicorn.”

The state Democratic Party reviewed his attendance records this summer, alleging that Toomey had missed seven of eight hearings or meetings on Iran that the Banking Committee held between 2011 to 2014.

Toomey's campaign said he was attending other meetings, including one with Treasury Secretary Jacob J. Lew, and a Finance Committee markup.

Democrats have also attacked Ohio Sen. Rob Portman and New Hampshire Sen. Kelly Ayotte for missing Homeland Security hearings.

In the rare race where both candidates have Senate records, Wisconsin Republican Sen. Ron Johnson and Democratic former Sen. Russ Feingold have both been criticized for their committee attendance — Johnson for missing Homeland Security hearings and Feingold for missing Foreign Relations hearings.

Attendance attacks have dogged Florida Sen. Marco Rubio for much of the year, going back to his failed GOP presidential bid. He’s missed nearly half the Foreign Relations hearings that dealt primarily with Iran in the 114th Congress, according to a recent Miami Herald report. Democrats pounced on him for missing a hearing to announce his belated decision to seek re-election.

Rubio has argued that his staff briefs him on missed hearings, and that most intelligence information he needs to know is communicated through reports rather than at the hearings. But his Democratic opponent, Rep. Patrick Murphy, has used Rubio’s missed hearings and votes to paint a broader narrative about Rubio not showing up for work.

"It’s really surprising that so many Republican senators couldn’t be bothered to show up to hearings, if not to actually do their jobs, then because they saw the issue used against Democrats recently," said a Democrat involved with Senate races.

When attacked, Republicans frequently counter with the same defense that Democrats have used: They were attending other, potentially more important, hearings and meetings.

Back in 2014, GOP consultant Paul Shumaker was looking for a good hit on Hagan, who’d been pummeling his client, then state House Speaker Thom Tillis, on education — an issue that resonated with the white female voters both candidates needed.

What else was a top issue for that demographic? Foreign affairs.

Shumaker heard that Hagan had missed an Armed Services briefing on ISIS to attend a fundraiser. He didn’t have confirmation, but his team developed an ad to test the message with a focus group of suburban women. When the spot made women who’d been leaning toward Hagan doubt her, Shumaker knew he’d found his issue.

Pressed on the issue at a post-debate press conference, Hagan admitted that she had missed one hearing to attend a fundraiser because the hearing was postponed. Crossroads GPS followed up with its own ad using Hagan's comments.

From Shumaker’s perspective, the incident was the turning point in the campaign. But it wasn’t simply that Hagan had missed a hearing that made the attack effective. It was the entire “mixed cocktail,” he said, that tapped into voter anxiety about ISIS and antipathy toward fundraising.

“It’s not just attendance records and how many missed,” Shumaker said, “but what did they miss?”

Attacking a senator for missing a Commerce Committee hearing, for example, may resonate less with voters than a hearing on a specific national security issue, said one Democratic operative who’s worked on Senate races.

And in an era when skepticism of the Washington establishment is already high, attacking senators for shirking their official duties may not be as potent a hit as it once may have been, Republican strategist Steve Gordon suggested.

“The average guy or gal on main street says, ‘Are you kidding? Most of those meetings aren’t worth a tinker’s damn anyway so why would anyone want to go?” Gordon said.

Being highly engaged back home can help mitigate those attacks, too.

“If Incumbent X is known for being present in his or her district, holding town meetings, and delivering some results from Washington, an attack on missing committee votes is likely to fall flat,” Democratic media consultant J.J. Balaban said.

Voters deserve some credit for understanding how busy their lawmakers are and that they can’t possibly get to everything, Democratic strategist Rick Ridder said. “We see it in our own lives. We don’t always make it to every kid’s soccer practice, every game, every meeting.”

He said voters are more sympathetic to missed committee hearings than they are to missed votes in the chamber, another frequent political attack point.

“But the real question is, is the committee absenteeism indicative of other forms of negligence?” Ridder said.

Operatives from both parties agree that when the attacker can establish a pattern, either about misplaced priorities or hypocrisy, these criticisms can stick.

Democrats, for example, are using missed committee hearings to go after Republicans’ perceived strength on national security. Since they're largely on offense this year, they can point to incumbents’ absenteeism to call into question just how seriously they take Iran or ISIS.

And next cycle, when Republicans are again on offense, look for them to do the same.

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Senate Minority Leader Harry Reid said Monday that Donald Trump is a racist, and lambasted the media for not labeling the Republican presidential nominee as such.

"There's always one word that many in the press conspicuously avoid: racist. … But he is a racist. Donald Trump is a racist," Reid said on the Senate floor. "'Racist' is a term I don't throw around lightly."

Reid has frequently taken to the floor to rail against the real estate mogul, and he recently criticized Trump's reluctance to release his tax returns and he alleged misconduct at the Trump Foundation.

[It's On Between Harry Reid and Donald Trump]

Reid said the media is not holding Trump accountable for his statements. He cited reports that Trump was discriminatory and derogatory toward minority employees, and his role in the so-called birther movement, which raised questions about whether President Barack Obama was born in the United States.

Reid also pointed to Trump's rhetoric about Muslims, and his remarks on a federal judge overseeing a Trump University lawsuit, which Speaker Paul D. Ryan called the "textbook definition of a racist comment." Reid criticized Ryan and and other Republicans for backing Trump's presidential bid.

"Think of the example Republicans are setting for our nation's youth," the minority leader said. "Republicans are normalizing racist behavior."

On Monday, Reid went where he declined to go 10 days ago during an interview on CNN. Asked on Sept. 16 if Trump is racist, Reid said, "I don't know. All you guys have a job to do. You make that decision. I'm not going to. I'm just telling you what he's done and we've seen it. He's a man of no morality."

Reid's comments come hours before Trump and his Democratic rival Hillary Clinton face off in the first general election debate.

Contact Bowman at bridgetbowman@rollcall.com and follow her on Twitter @bridgetbhc.

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