One of the primary benefits of being a first-term incumbent president is that you don't have to worry about a primary challenge. Traditionally, the incumbent is able to focus all their energy on the general election, while, of course, maintaining their presidential duties.

But former Florida Gov. Jeb Bush, who ran for the Republican presidential nomination in 2016, says a Republican should challenge Trump in 2020.

What are the details?

While speaking with David Axelrod on CNN's "The Axe Files" over the weekend, Bush argued that a Republican challenger would give Republicans and conservatives "a choice."

"I think someone should run just because Republicans ought to be given a choice," Bush said. "It's hard to beat a sitting president, but to have a conversation about what it is to be a conservative, I think it's important."

"And our country needs to have competing ideologies that people — that are dynamic, that focus on the world we're in and the world we're moving towards rather than revert back to a nostalgic time," Bush explained.

Bush made his comments during a discussion about Maryland Gov. Larry Hogan, a moderate Republican who hinted last month that he is considering a presidential run.

"People are talking to me about it," Hogan told CNN. "I'm flattered people are saying that and including me in those discussions. My focus, my plan right now is to stay here for four years and do the best job I can in Maryland, but I've said, 'You never say never.' Who knows what's going to happen."

So far, no Republican has committed to challenge Trump. However, former Ohio Gov. John Kasich, who finished second to Trump in the 2016 Republican primary, is reportedly exploring an independent challenge.