Trump remains noncommittal on 2028 Republican nominee as Vance and Rubio prepare

Vice President JD Vance and Secretary of State Marco Rubio are the two most frequently mentioned candidates among party voters. Voters at a June 24 Trump rally on the National Mall said an endorsement from the president would influence their choice. One attendee, Vicki Schwartz, said she would support either candidate if Trump selected one.

Vance's visibility Vance has promoted his new book "Communion" and conducted interviews tied to Iran peace negotiations. He told USA TODAY in June that he remains focused on the vice presidency and the November midterms. Vance has described himself as both an economic populist and a religious conservative.

He supports state-level bans on holiday business openings and the right of workers to unionize.

Rubio's standing Rubio, a former Florida senator, has advised Trump on international affairs. An Emerson College survey of Republican voters released in May showed Vance at 36 percent and Rubio at 35 percent. Trump has asked associates privately about both men for at least a year.

He has also publicly polled audiences on their preferences while stating that the questions do not signal an endorsement.

Iran negotiations Vance traveled overseas in June to meet Iranian leaders.

Trump praised his performance on June 22 and said on June 17 that Vance would be responsible if the talks fail. People close to the White House said a weak Iran agreement could hurt Vance's prospects while a strong one could strengthen them.