If, as now seems likely, the U.S. House of Representatives votes to impeach the president, some Democrats worry that the Senate will find President Trump not guilty of all charges — and that will only help him. These analysts believe that the GOP’s overwhelmingly partisan vote to impeach Bill Clinton backfired when the Senate failed to convict, hurting only the Republicans.

New York Times columnist David Leonhardt recently challenged that view. He argued that although voters approved of Clinton’s job performance, they disapproved of his personal behavior — and that damaged Al Gore’s campaign.

Leonhardt argues that the lesson is that impeachment — which indicts Trump for and draws attention to his unethical behavior — will hurt him at the polls in 2020, regardless of how the Senate votes.

Is he right about the evidence from 2000? My research supports Leonhardt’s conclusion: Survey evidence strongly shows that Clinton was an albatross for the Gore campaign. I’ll explain below.

Gore ran from Clinton’s reputation in his campaign. Clinton thought his record would have been an asset.

In November 2000, shortly after Al Gore conceded defeat, he and Clinton had a contentious meeting blaming each other for the Democrats’ loss of the White House, according to Washington Post reporting. Gore had failed to involve Clinton in the 2000 campaign and had even been reluctant to invoke the administration’s record. He viewed Clinton’s personal misbehavior as a serious and inescapable problem.

It’s hard, now, to fathom how much the Lewinsky scandal and Ken Starr’s detailed report damaged Clinton’s character ratings. The 2000 American National Election Study (ANES) found that an astonishing 70 percent of voters said the term “dishonest” described Bill Clinton either extremely well or quite well; only 19 percent felt that about George W. Bush. If Clinton was distrusted, how would it have helped the Gore campaign to get his public blessing? To make matters worse, only 12 percent of voters said Clinton was “moral,” a major problem in an era when major candidates ran heavily on “family values.”

But Gore’s decision to distance himself from the administration irked the outgoing president. Clinton thought he’d left Gore a good shot at victory, with a booming U.S. economy. And he thought he could have turned the tide if Gore had let him campaign. Despite the public distaste for him personally, Clinton thought that he’d have been an asset, given high public approval ratings for his job performance.

Which one of them was right?

ANES offers a good measure of overall public attitudes in its 0-100 “feeling thermometer.” Comparing candidates’ feeling thermometer ratings is an excellent predictor of voting behavior; Americans almost always vote for the candidate that they’ve given the higher thermometer rating to. The figure below presents simulations for how Presidents Lyndon B. Johnson, Ronald Reagan, Clinton, George W. Bush and Barack Obama, as they left office, would have fared against the opposing party’s nominee to replace them, using these thermometer ratings at that time.

The impeachment inquiry hurt Clinton — and probably tarnished Gore as well

The results support Gore’s decision to minimize his association with Clinton. A Clinton-Bush 2000 matchup would have been close. But in reality, Gore beat Bush in the popular vote — and Clinton would have failed to do so. By this measure, Clinton was clearly less of a liability than LBJ was against Nixon in 1968, or than George W. Bush was against Obama in 2008.

But even though Clinton’s job approval ratings in 2000 were nearly identical to Reagan’s in 1988, he was not the same kind of electoral asset. Nor was Clinton the asset that Obama was to Hillary Clinton in 2016. The whole scandal — from the first news of the affair, to the special prosecutor’s damaging report, to the impeachment vote, and finally to the Senate trial, all damaged Clinton’s image. Even a not-guilty verdict in the Senate couldn’t erase the stain on Clinton, and by association the Democrats.

Of course, we can’t automatically assume that Clinton’s integrity affected how Americans voted in 2000. After all, he wasn’t on the ballot. But I used a multivariate model of the 2000 vote — and found that how Americans responded to a question about Clinton’s impact on the nation’s moral climate were strongly related to how they voted, even after controlling for a variety of other factors. In fact, this had a greater influence on voting than responses to a similarly worded question about Clinton’s impact on the economy.

In short, George W. Bush’s strategy of repeatedly pledging to “restore dignity and honor to the White House” worked as intended.

So what’s the real lesson from Clinton’s impeachment?

As Leonhardt argues, impeachment without a conviction nevertheless aids the opposition party by throwing a spotlight on the incumbent’s misdeeds in office. By changing the focus from economic performance to personal integrity, the Republicans put themselves in a much better position to win in 2000. Even if all the current impeachment inquiry succeeds in doing is drawing attention to Trump’s faults, it should still help the Democrats in 2020.

Martin Wattenberg is professor of political science at the University of California at Irvine and author of “Is Voting for Young People?” (Routledge, 2016).

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