South Dakota’s John Thune, McConnell’s current No. 2, and John Cornyn of Texas, who held that job before Thune, are the front-runners in the Nov. 13 secret ballot to replace McConnell. The Kentucky senator is stepping aside from the post in January after almost two decades as leader. The winner could steer the direction of the party for years to come and possibly become the next Senate majority leader if Republicans win enough seats in Tuesday’s election.

The outcome is, for now, uncertain.

Only a few Republican senators have publicly endorsed a candidate. Many say they are still undecided. The third senator in the race — Florida Sen. Rick Scott, who is dealing with his own reelection bid — could act as a spoiler. Another candidate could still jump in.

In many ways, “the two Johns” are remarkably similar, making the choice difficult for their colleagues. Both are well-liked and, in the mold of McConnell, lean toward the more traditional wing of the Republican Party. But both have also suggested they will try to move on from the McConnell era with a more open approach.

“I’m trying to find differentiation because they’re both great guys,” said Sen. Thom Tillis, R-N.C., who has worked closely with both of them.

The two men are also trying to distinguish themselves from McConnell by making clear that they support Donald Trump in this year’s presidential election. Like McConnell, they have both sparred with Trump in the past, especially after the Jan. 6, 2021, attack on the Capitol. But both Thune and Cornyn have talked to Trump frequently in recent months, attended campaign events and visited his Florida home.

Whether Trump wins, and if he endorses one of the contenders, could become a determining factor.

“I don’t know what he’ll do,” Cornyn said of Trump in September. “But this is obviously an election between senators, and I think that’s where the voters are.”

Some of the former president’s strongest allies in the Senate are urging him to stay above the fray. Oklahoma Sen. Markwayne Mullin, who is supporting Thune, says he’s been trying to talk Trump out of an endorsement. Trump understands “the need to work with whoever the next leader is,” Mullin said.

Tillis suggested that a Trump endorsement could backfire.

“You have to be careful with the psychology of the Senate,” Tillis said. “We know each other very well, and we spend hours and hours together. It’s a fairly small club.”

Still, both Cornyn and Thune are keeping close to Trump. Cornyn met Trump on a trip to Texas in October and appeared at a rally in Nevada. Thune was at an event in August with Trump’s running mate, Ohio Sen. J.D. Vance.

Thune, who said after the Jan. 6 attack that Trump’s efforts to disrupt the peaceful transfer of power were “inexcusable,” told The Associated Press over the summer that he views their potential relationship as a professional one. If they both win their elections, Thune said, “we’ve got a job to do.”

Scott, meanwhile, is a longtime friend of Trump’s and has positioned himself as a strong ally. Scott traveled to New York to support Trump during Trump’s hush money trial. Trump could endorse Scott in the contest, potentially winning more votes for the Florida senator or giving him leverage to influence the race.

In addition to private meetings, both Thune and Cornyn have flown around the country to fundraise and campaign for their fellow senators.

Thune has made more than two dozen campaign stops for GOP senate candidates, and aides say he has raised more than $31 million for Senate races this campaign cycle, including a $4 million transfer to the Senate Republican campaign operation.

Cornyn has similarly gone around for candidates and poured money into Texas races. His aides emphasize his long history of fundraising for Republicans — more than $400 million during his 22 years in the Senate, his office says.

On policy, the two men are similar, voting generally in step with the conference but working with Democrats at times. Cornyn is a longtime member of the Senate Judiciary Committee who took a leading role on bipartisan gun legislation two years ago. Thune worked across the aisle as a former chairman of the Senate Commerce, Science and Transportation Committee.

It’s unclear whether either could win support from the growing minority of Republican senators who battled McConnell in recent years as he championed Ukraine aid and criticized Trump. Many in that group voted for Scott when he challenged McConnell after the 2022 elections.

In a potential overture to that group, Cornyn has called for a conference vote on instituting term limits for the Republican leader. “I believe the Senate needs more engagement from my colleagues, and that includes the opportunity for any member to serve in leadership,” Cornyn posted on X in March.

Missouri Sen. Josh Hawley, a member of the more conservative faction, said he has not made a commitment in the race but wants to know how they would move legislation and work with Trump if he is president. “I think some of this will come into focus after the election when we know what we’re dealing with, we know what our caucus is going to be,” Hawley said.

Many in that group, including Scott and Utah Sen. Mike Lee, have pushed to take power away from leadership and empower individual senators. Lee has issued a series of candidate demands, but neither Cornyn nor Thune has so far shown interest in negotiating.

But both of them have signaled that they hear the complaints.

Thune indicated in the AP interview that he’s open to making changes to the leader’s role, but cautioned that he would not leave the position at the mercy of rank-and-file senators. He said he wanted to “empower our individual members or committees to do things through regular order” and open up the amendment process, but “I’m not going to make wholesale changes that weaken the leader position to where it’s just a free-for-all.”

Tillis suggested in September that it would be a deal breaker for him if any of the candidates engaged in deal-making.

“If you would be willing to weaken your position to satisfy a few votes, then you’re unfit to be leader, in my opinion,” Tillis said. “And I think most people think that way.”