Ms. Cheney said she had no interest in changing parties: “I’m a Republican.” But when asked if the G.O.P. she was raised in was even salvageable in the short term, she said: “It may not be” and called her party “very sick.”…

Ms. Cheney suggested she was animated as much by Trumpism as Mr. Trump himself. She could support a Republican for president in 2024, she said, but her redline is a refusal to state clearly that Mr. Trump lost a legitimate election in 2020.

Asked if the ranks of off-limits candidates included Gov. Ron DeSantis of Florida, whom many Republicans have latched onto as a Trump alternative, she said she “would find it very difficult” to support Mr. DeSantis in a general election.

“I think that Ron DeSantis has lined himself up almost entirely with Donald Trump, and I think that’s very dangerous,” Ms. Cheney said.