WASHINGTON (NEXSTAR) – Republicans are threatening legal challenges over President Joe Biden’s decision to leave the race but legal experts say those are unlikely to be successful. 

Just before President Biden dropped out of the race on Sunday, House Speaker Mike Johnson (R-La.) told ABC News his withdrawal would raise legal issues. 

“I think they’ve got legal trouble,” Johnson said. “These elections are handled at a state level. Every state has its own system, and in some of these, it’s not possible to simply just switch out a candidate.” 

Georgetown law professor Paul Smith is an expert in campaign law. He disagrees. 

“There’s really nothing Republicans can do as a legal matter to stop the switch from happening,” Smith said. 

He says Democrats don’t have a legal obligation to nominate President Biden. 

“He’s not on a ballot anywhere yet. He’s only a presumptive nominee before he pulled out,” Smith said. 

George Washington University Political Communications Professor Peter Loge agrees. He says the Democratic party has the power over their presidential ticket, not Republicans. 

“It’s not theirs to decide. It’s up to the Democrats to decide who the Democratic nominee is going to be. I think they’re trying to throw sand in the gears,” Loge said. 

The Democratic National Committee says it will have delegates vote through a virtual roll call to choose a nominee by August 7th. Vice President Kamala Harris has already secured the support of enough delegates that she’s expected to win during that vote. 

“As long as they do it on time and in the normal processes she’ll go on the ballot, and at that point the process is over,” Smith said. 

Republicans call it undemocratic to have delegates pick the new nominee. 

But Loge points out the Democratic primary elections are over, leaving the DNC with limited options. 

“In Republicans’ telling its fundamentally unfair. They have a point. You had a whole lot of people vote for a guy,” Loge said. “I think the DNC is trying to figure out the fairest, most transparent thing to do in really extraordinary circumstances.”

The Heritage Foundation also sent out a memo outlining how they believe President Biden exiting the race could lead to lawsuits, but they have yet to announce their own legal challenge.