Other rumoured White House contenders include Secretary of State Marco Rubio, Senator Ted Cruz of Texas, Florida Governor DeSantis, former US ambassador to the United Nations Nikki Haley and former New Jersey Governor Chris Christie, to name a few.

In the next election cycle, Republican presidential and congressional candidates alike will have tough decisions to make on key issues of the day, from US support for Israel to tariffs to the AI boom.

Trump's power may be diminished as he enters the final two years of his second term, but he'll still have the loudest voice in the party over the next two years. It's unclear whether he will get deeply involved in the process or take a hands-off approach.

Trump has praised Vance and Rubio at different times, but typically deflects questions about who he'd like to see succeed him.

His endorsement will loom as the biggest wildcard in the 2028 Republican primary race.

"It remains to be seen who will jump into that race," Ayres said.

"But I think it's going to be a lot larger and more diverse than we anticipated before the midterm election."

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