Editor’s Note: Joshua A. Douglas is a law professor at the University of Kentucky J. David Rosenberg College of Law. He is the author of “Vote for US: How to Take Back Our Elections and Change the Future of Voting.” Find him at www.joshuaadouglas.com and follow him on Twitter @JoshuaADouglas. The opinions expressed in this commentary are his own; view more opinion at CNN.

CNN  — 

In 2019, incumbent Republican Kentucky Gov. Matt Bevin was down in the vote totals to challenger Democrat Andy Beshear by about 5,000 votes out of around 1.4 million votes cast. But Bevin refused to concede, claiming unspecific election “irregularities,” with no evidence whatsoever.

Sound familiar?

Bevin acknowledged defeat only after several prominent Republicans told him to produce evidence of election fraud or else concede the race.

Joshua A. Douglas

Although nothing is official until state election authorities certify the results, the Electoral College votes on December 14 and Congress counts those votes on January 6, the continuing, lawful vote tabulation in several states suggests that Donald Trump has lost his bid for reelection. It is now time for leading Republicans, such as Sens. Mitch McConnell and Lindsey Graham, as well as former President George W. Bush, to speak up. They must demand that Trump cease his dangerous language that casts doubt on the legitimacy of the election and – unless he has real evidence – end his baseless lawsuits that seek only to further undermine people’s faith in the outcome.

The initial statement from McConnell on Wednesday was way too timid. Although he agreed that election officials must count all votes, he did not condemn Trump’s incendiary rhetoric about going to the Supreme Court to stop the count – a claim that has no reality in law or fact. McConnell declined to comment after Trump’s inflammatory news conference on Thursday night, in which Trump made wild, unfounded accusations of election fraud, saying, “They’re trying to steal an election, they’re trying to rig an election, and we can’t let that happen.” Graham, of South Carolina, even backed Trump’s lies.

Some Republicans have begun to distance themselves from Trump, but not boldly or unequivocally. Former New Jersey governor and Trump adviser Chris Christie merely said that there was “no basis” to make the argument on Tuesday night that Trump had won. Sen. Marco Rubio of Florida, without mentioning Trump by name, placidly tweeted, “The result of the presidential race will be known after every legally cast vote has been counted.” Former Pennsylvania Sen. Rick Santorum said that Trump’s language at Thursday’s news conference was “shocking,” but he did not wholly debunk Trump’s unfounded conspiracy theories – though he did at least say that the President should provide evidence of his claims.

But that’s not good enough. We need a strong and absolute rebuke of this undermining of American democracy from Trump’s most fervent supporters at the highest echelons of the Republican Party.

Of course, there’s no legal requirement that a candidate concede. So long as the official vote totals are consistent with current trends and projections, former Vice President Joe Biden will assume the presidency on January 20, 2021, regardless of what Trump says.

But a concession could help the country move forward in a peaceful manner. It could help Trump supporters recognize that he lost legitimately. And it could renew people’s faith in our electoral system.

That’s what happened last year in Kentucky. There was a week of political turmoil as some people floated the idea that Bevin would try to contest the election in the Republican-controlled legislature. Bevin continued to claim “irregularities,” suggesting that there were “thousands of absentee ballots that were illegally counted,” voters being “incorrectly turned away,” and “a number of machines that didn’t work properly.” But he had no evidence. Two Bevin voters then made unsubstantiated allegations of vote “hacking,” again without evidence – though Bevin promoted the voters’ news conference.

But then prominent Kentuckians – as well as journalists and others – spoke out, ultimately leading Bevin to back off.

The same needs to occur now. Trump has signaled for months that he would not accept defeat. He said that in 2016, too.

But the situation is different now because, it appears, Trump has lost. The question of whether he will agree to a peaceful transfer of power is now squarely before us.

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It’s not enough for Democrats to oppose Trump’s delegitimizing language. They have been doing it for years. It is not enough for journalists or election law professors to explain why Trump’s message is so dangerous.

Republicans need to make a choice: How much do they value American democracy and the norms that must sustain it? The longer they wait, the longer Trump can create chaos among his supporters. The longer they wait, the more doubt he sows about the true winner of this election. The longer they wait, the more fragile our institutions will become.