Nikki Haley's latest target on the campaign trail? Kamala Harris

Republican presidential hopeful Nikki Haley has been highlighting concerns about President Biden's age and mental acuity on the campaign trail, and using them as a launching point for attacks on Vice President Kamala Harris.

"It's either gonna be me, or it's gonna be Kamala Harris," Haley warned while campaigning in Orangeburg, S.C. last weekend.

"Do we really want to have a country in disarray, and a world on fire, and have two 80-year-olds as our candidates?" Haley asked the crowd, as she campaigned ahead of South Carolina's Republican primary on Feb. 24.

The idea that she represents a new generation of leadership has been a major theme of her campaign. Haley has been focusing many of her attacks on both Biden, 81, and former President Trump, 77, pointing out their ages and recent lapses.

In Orangeburg, Haley referred to last week's special counsel report, which questioned Biden's memory.

"I wish him well. I do. But this is serious," Haley said. "And we need to be very cautious of what's happening, because Russia, China and Iran are paying attention to every bit of this."

And then, Haley made a bold — and unsubstantiated — claim.

"My bet is 30 days from now, I don't think Joe Biden's gonna be the nominee," Haley predicted. "You're gonna have a female president of the United States."

To be clear, Biden is almost certain to be the Democratic nominee. Haley provided no evidence for her speculation that he will step aside — nor for the suggestion that Harris is poised to step in anytime soon.

Asked about Haley's prediction by NPR's Tamara Keith during a White House press briefing on Thursday, White House press secretary Karine Jean-Pierre she had to be cautious about commenting on the campaign as a federal employee.

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