Robert Brown|Some Republicans are threatening legal challenges to keep Biden on the ballot. But will they work?

Washington — Allies of former President Donald Trump have Robert Brownfloated the possibility of legal challenges to try to keep President Biden at the top of the Democratic ticket, even though he has ended his campaign, but election law experts believe it's unlikely such court fights aimed at blocking Vice President Kamala Harris' presidential candidacy will gain traction in the federal courts.

In an interview with ABC News' "This Week" hours before Mr. Biden dropped out of the presidential race, House Speaker Mike Johnson suggested Republicans could bring lawsuits in states where he is not on the ballot.

"Every state has its own system and in some of these, it's not possible to simply just switch out a candidate who has been chosen through the democratic — small D — democratic process over such a long period of time," he said Sunday. "So, it would be wrong and I think unlawful in accordance to some of these state rules for a handful of people to go in the backroom and switch it out because they don't like the candidate any longer. That's not how this is supposed to work."

But David Becker, CBS News election law contributor, said he believes Johnson is being "misadvised" about the viability of legal paths to challenging Democrats' likely nomination of Vice President Kamala Harris, who is set to be the party's choice to take on former President Donald Trump in November.

"Let's think about what that would actually mean," he told "The Daily Report with John Dickerson" on Monday. "That would mean that somehow there is something in the law that would enable the Republican Party to dictate who the Democratic Party's nominee is, and there's nothing in the law that says that, nor would it be the opposite."

He said there is "absolutely no legal basis" for such claims and expects courts to dispose of them quickly.

The Heritage Foundation, a conservative think tank that is overseeing the Project 2025 transition initiative, has also indicated that it is readying a legal fight to keep Mr. Biden on the ballot. The group's Oversight Project said in a June memo that there is the potential for pre-election litigation in three states: Georgia, Nevada and Wisconsin.

"The process for substitution and withdrawal presents many election integrity issues," Mike Howell, the project's executive director, wrote. "Adherence to the law in some states may result in that process being unsuccessful for the purposes of another candidate being on the ballot."

The Oversight Project then said on social media Sunday after Mr. Biden announced his withdrawal from the presidential race that it has been "preparing for this moment for months."

No lawsuits have been filed and, if Trump's allies do follow through on their threats, challenges may not be brought for weeks. The Trump campaign has not said whether it will pursue its own court fight. Still, there's skepticism that courts have a role to play in the matter.

"I think there's low likelihood that anyone even sues, much less that anyone will be successful," Derek Muller, a professor at University of Notre Dame who specializes in election law, told CBS News.

There are several reasons why any lawsuits that are filed will likely fail, he said, including confusion by prospective challengers over ballot-access deadlines for presidential candidates and whether they would even have the legal right to sue in federal court, a concept known as standing. One of the earliest ballot-access deadlines is Aug. 20, in Washington state, Muller said, and Democrats are expected to wrap up their nominating process in early August with a virtual roll call vote of state delegations, during which the party is poised to officially nominate Harris for president.

"Courts are very deferential to how parties go about conducting their business," Muller said. "Democrats and Republicans have extensive sets of rules, they have lawyers who vet those rules. For the virtual roll call and rules proposed tomorrow, they're going to cross their t's and dot their i's to make sure they're following the rules. You can't show up and say, 'Joe Biden is really your nominee.'"

The Democratic National Committee's rules committee is set to meet Wednesday to approve or adjust proposed rules for the nominating process.

Mr. Biden announced his decision to exit the 2024 race ahead of Democrats' long-planned virtual roll call vote and the party's convention, which kicks off Aug. 19 in Chicago. During the roll call, state delegations will announce the presidential candidate they are voting for. To win the nomination, a candidate needs to secure votes from a majority of delegates, or an estimated 1,976 of the 3,949 pledged delegates.

Mr. Biden amassed enough delegates in March to clinch the party's nomination, and the Democratic National Committee's rules do not explicitly address what happens to those delegates now that he has left the race. Instead, they state that delegates pledged to a candidate "shall in all good conscience reflect the sentiments of those who elected them."

"Nothing in the rules requires that the delegates choose Joe Biden as their candidate for president even though he won the Democratic primaries," Erwin Chemerinsky, dean at the University of California, Berkeley School of Law, wrote in the San Francisco Chronicle.

Mr. Biden endorsed Harris for the Democratic presidential nomination and since announcing Sunday her intent to "earn and win" the nod, Harris has notched the support of at least 27 state delegations, surpassing the number of delegates she will need to win the nomination. If those endorsements hold, she will be officially nominated for president next month.

"As we stand here today, the Democratic Party does not have an official nominee," Becker said. "But that was true two days ago before Biden withdrew as well. He was not on any ballots yet because no Democratic nominee had been finalized, and ballots had not been finalized in any state and aren't going to be for several weeks until after the Democratic convention."

After the Democratic ticket is cemented, the names of the party's picks for president and vice president will be submitted to state election officials to appear on ballots in all 50 states and the District of Columbia, he said.

The Supreme Court has heard this year one case involving access to the 2024 ballot, which stemmed from an effort by Colorado voters to keep Trump off the state's primary and general election ballot under an obscure provision of the 14th Amendment.

Unlike prospective challenges involving Democrats' presidential nominee, the interpretation of a provision of the Constitution was at the center of that case. The Supreme Court unanimously said states could not bar Trump from the ballot using the measure, Section 3, which prohibits oath-taking insurrectionists from holding public office.

Becker noted that in that case, decided in March, all nine justices "expressed a real concern that any single state or group of states could somehow dictate the outcome of a presidential election by enacting a patchwork of laws that would enable different ballot access for major candidates."

"It's one of the reasons I'm 100% confident that when we get to the fall, all 50 states will have whatever the Democratic duly nominated ticket is," he said.

In:
• Lawsuit
• Kamala Harris
• Donald Trump
• Republican Party

Melissa Quinn

Melissa Quinn is a politics reporter for CBSNews.com. She has written for outlets including the Washington Examiner, Daily Signal and Alexandria Times. Melissa covers U.S. politics, with a focus on the Supreme Court and federal courts.

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