Donald Trump fears longshot Republican opponent Vivek Ramaswamy will cut into a pivotal voter bloc for the former president, according to a new report.

Tom LoBianco, political reporter for 24sight and biographer of former Vice President Mike Pence, spoke with Trump insiders about campaign worries ahead of the Iowa Caucus.

“Simmering just beneath the surface has been a worry among Trump and some on his team that Ramaswamy will eat into Trump’s margin of victory Monday night, particularly among a key subset of voters,” LoBianco writes. "Young men."

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“Trump wants him out now,” one Trump adviser told the reporter.

While Trump remains a strong frontrunner among conservatives hoping to claim the White House in the November election, concerns linger over the damage Ramaswamy could do with easy access to campaign cash, according to the report.

Pollster Michael Cohen (not the former Trump lawyer) confirmed Trump and Ramaswamy share a core, “coveted” constituency group.

“The demographic is men,” Cohen told 24sight. “Young MAGA men.”

Ramaswamy likely won't be among the top three in Iowa Monday night, but experts believe any votes he claims would otherwise have gone to Trump, LoBianco notes. And the lower Trump’s victory margin, the more likely competitors will linger to battle it out in upcoming caucuses and primaries.

“Ramaswamy wasn’t an issue when there were a dozen or more candidates in the field,” LoBianco writes. “But as the race whittled down to three or four serious candidates, it’s now a problem for Trump.”

Read the full analysis here.