Sidelined: How the Trump-DeSantis face-off is causing chaos in the GOP
SUNRISE, FLORIDA - Donald Trump introduces Florida Governor Ron DeSantis during a homecoming campaign rally at the BB&T; Center on November 26, 2019 in Sunrise, Florida. (Photo by Joe Raedle/Getty Images)

The 2024 Republican presidential field is coming together more slowly than expected after Donald Trump became the first to jump into the race.

So far the only serious would-be challengers seem to be Ron DeSantis, Nikki Haley, Mike Pence and Mike Pompeo -- although none of them have officially announced -- but Republican insiders are surprised by how many potential candidates remain on the fence or are planning to sit out of the 2024 primary race, reported Politico.

“I would’ve told you last fall that there would be five senators in the race,” said GOP strategist Ward Baker, who says he put together a presentation projecting at least 10 candidates in the race.

Trump won the 2016 nomination thanks in part to a large and splintered primary field, and GOP strategists expected the same dynamic could play out in this race, but Baker and other insiders believe only seven or eight serious candidates -- or even smaller -- could remain when Republicans first head to the polls a year from now.

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“They don’t have a Trump problem, they have a DeSantis problem,” said GOP strategist Scott Jennings. “It’s going to be hard fighting for the other 60 to 70 percent of the vote [not going to Trump] when another guy could get 90 percent of it.”

DeSantis is already polling strongly against the former president, who seems to recognize his growing popularity with the base, and that two-man dynamic may be freezing out the senators, governors and others who might otherwise throw their hats into the ring.

“Do you want a Trump or DeSantis, or do you want a Mitt Romney or a Liz Cheney?” said far-right Mississippi state Sen. Chris McDaniel, as he announced his campaign for lieutenant governor last week by tying himself to the party's standard bearers.

That seems to be keeping a whole generation of contenders -- Rick Scott, Tom Cotton, Josh Hawley, Glenn Youngkin, Brian Kemp and Larry Hogan -- on the sidelines, because challenging the two figures most popular with the GOP base could hurt them in their re-election campaigns if they didn't win the presidential nomination.

“There’s a sensitivity to his base in the sense that 30 percent of them will be with him and we need everyone at the end of the day,” said RNC member Luis Fortuño, the former Puerto Rico governor.