Who might replace Mitch McConnell as the top Senate Republican?

With Senate Republican leader Mitch McConnell announcing Wednesday his plans to relinquish his leadership role in November, speculation is swirling about what will happen next and who might fill his shoes.

McConnell will be leaving a post he's held for about 17 years. And while his announcement Wednesday caught some by surprise, a behind-the-scenes race to replace him and chart a new path for the Senate Republican Conference has been percolating for months and will likely now break into full view.

After the 2024 election, but before newly elected members are sworn in, there will be closed-door Senate Republican Conference meeting in which members will nominate and elect a new leader.

There are three major contenders largely expected to vie for the top spot: the "three Johns," as some have called them, are Sens. John Thune, John Barrasso and John Cornyn.

John Thune

Thune is currently the No. 2 Senate Republican and serves as the minority whip. The South Dakota Republican is largely seen as having been groomed by McConnell for the role, but given McConnell's waning popularity with the far-right flank of his party, it remains to be seen whether this helps or hurts his chances.

Thune was once a fairly outspoken critic of former President Donald Trump, but ultimately endorsed him for president on Monday after his win South Carolina's GOP primary.

John Barrasso

Barrasso, a Wyoming Republican, is the No. 3 Senate Republican. Barrasso has the most conservative voting record of the three lead contenders, and was the first of the first of the three to endorse Trump's 2024 run -- doing so in January.

John Cornyn

Cornyn, a Texas Republican, was once the Republican whip but termed out of the role after serving in it for six years. He is still considered part of McConnell's leadership team.

Cornyn toes the party line most of the time, but notably joined with Democrats to pass the bipartisan gun safety act last Congress, making him the target of fierce criticism in the state.

None of these men has yet made their intentions clear. Walking off the floor moments after McConnell's speech announcing that he would step down, Thune said McConnell "leaves really big shoes to fill."

"We'll give you more, I think, insight into what we're thinking here in the near future. Kind of want to just today honor him," Thune said.

Barrasso said the focus should be on another contest: the 2024 presidential election.

"There's a much more important election between now and November," Barrasso said.

It's very possible there could be a dark horse candidate as well. Last year, Sen. Rick Scott challenged McConnell for the seat he currently holds -- the first time McConnell had faced a leadership challenge. The Florida Republican lost to McConnell 37-10.