President-elect Donald Trump will begin serving his nonconsecutive second four-year term in January but is constitutionally barred from seeking a third term in office in 2028, which raises the question of who will succeed him as the leader of the Republican Party.

By virtue of his role as Trump's running mate and second-in-command, Vice President-elect JD Vance will almost certainly be the frontrunner in a potentially large field of challengers to follow in Trump's wake once he steps aside, according to Fox News.

Yet, while Vance will likely enjoy an incumbency advantage over other GOP contenders in 2028, there promises to be substantial competition for the party's nomination, to say nothing of the crop of likely Democratic candidates who will try to retake the White House for their party in the next election cycle.

Vance the presumptive frontrunner

"The vice president will be in the catbird seat. No question about it," GOP consultant Dave Carney, who labeled Sen. Vance (R-OH) the "guy to beat" in 2028, told Fox News. Yet, Republicans also have a "deep bench" of presidential contenders who will keep watch for "opportunities" to exploit to further their own ambitions if the next four years go poorly for the Trump-Vance administration.

Carney suggested that "there may be other people who challenge him [Vance] … there’s a lot of people who want to be president, but it will be a very hard lane other than the Trump lane." Even still, the consultant predicted that Vance would be "the guy to beat, regardless of whether it’s a good four years or a rough four years."

GOP strategist David Kochel agreed with that sentiment and said Vance is the frontrunner by default because of "the size and the scope of last week's victory and the implied passing of the torch from Donald Trump."

"There will be no shortage of people looking at it. But most people looking at it are seeing the relative strength of the Trump victory and the movement," he added, and though Vance will presumably enjoy an inside track toward the 2028 nomination, "nobody will completely defer to JD Vance. There will be a contest. There always is."

Possible Republican contenders

According to Fox News, some of the most likely top contenders to challenge Vice President-elect Vance for the GOP nomination in 2028 include a trio of popular governors like Florida's Ron DeSantis, Georgia's Brian Kemp, and Virginia's Glenn Youngkin. There is also a trio of GOP senators who could make a run, such as Ted Cruz of Texas, Tom Cotton of Arkansas, and Josh Hawley of Missouri.

Following that top tier, other possible challengers include former Ambassador Nikki Haley, Arkansas Gov. Sarah Huckabee Sanders, and business entrepreneur Vivek Ramaswamy, along with Sens. Marco Rubio of Florida, Tim Scott of South Carolina, and Rick Scott of Florida.

The field could grow even larger with potential candidates like former Secretary of State Mike Pompeo, Reps. Byron Donalds of Florida and Elise Stefanik of New York, and South Dakota Gov. Kristi Noem, to say nothing of President-elect Trump's biological heir, Donald Trump Jr.

Newsweek reported speculatively on the possible field of Republican contenders in 2028 and similarly mentioned Vance, Haley, DeSantis, Kemp, and Sanders, but also added to the mix Texas Gov. Greg Abbott and Republican National Committee co-chair Lara Trump, the president-elect's daughter-in-law.

More than a dozen possible Democratic challengers

Of course, the Democratic Party will also be vying to regain the White House, and Politico reported that Vice President Kamala Harris and Minnesota Gov. Tim Walz, despite their loss last week to the Trump-Vance ticket, will possibly make their own separate second bids for the White House in 2028, albeit perhaps not at the front of the pack, though.

The presumptive frontrunner for Democrats right now is California Gov. Gavin Newsom, but he will be followed closely by other governors like Pennsylvania's Josh Shapiro, Michigan's Gretchen Whitmer, Kentucky's Andy Beshear, Illinois' JB Pritzker, and Maryland's Wes Moore.

Other likely contenders include Transportation Sec. Pete Buttigieg, Sens. Amy Klobuchar of Minnesota, Cory Booker of New Jersey, Michael Bennet of Colorado, and even John Fetterman of Pennsylvania, along with Rep. Ro Khanna of California, among plenty of others.