Former Sen. Jeff Flake announced Tuesday that he will not launch a primary campaign in 2020 against President Trump, and instead signed on as a contributor at CBS News.

The former Arizona Republican made the announcement on CBS in his first appearance in his new role at the network, and said he hopes someone still challenges the president.

"I've always said that I do hope that there is a Republican who challenges the president in a primary," Flake said. "I still hope that somebody does, but that somebody won't be me. I will not be a candidate."

"There really isn't a path right now that I can see," Flake said, referring to a possible Republican challenger. "Not unless you're willing to be out there already raising a lot of money and basically living on the road right now. It's a difficult path anyway. The RNC and the president's campaign are now melded. They're trying to do everything they can to squelch any opposition."

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"I still hope that some — and some are still talking about it — do run," he added. "I think that that's healthy, and I'm not a fan of this president."

Flake had toyed with a potential run after making multiple trips to New Hampshire in 2018 before exiting the Senate in January.

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