Senator Jeff Flake of Arizona will not run for re-election

WASHINGTON, DC - MAY 25: Sen. Jeff Flake (R-AZ) (L) and Sen. Tim Kaine (D-VA) talk about their introduction of a new Authorization for the Use of Military Force (AUMF) against the Islamic State of Iraq and Syria (ISIS), al-Qaeda and the Taliban during a news conference at the U.S. Capitol May 25, 2017 in Washington, DC. The new AUMF would repeal and replace Congress' 2001 and 2002 authorizations while expanding the list of terrorist organizations that the U.S. can take military action against. (Photo by Chip Somodevilla/Getty Images)

WASHINGTON  — Republican Sen. Jeff Flake of Arizona will not run for re-election, saying Tuesday he wouldn’t embrace President Donald Trump to win next year’s Republican primary.

“Here’s the bottom line: The path that I would have to travel to get the Republican nomination is a path I’m not willing to take, and that I can’t in good conscience take,” Flake told The Arizona Republic.

He intends to detail his decision to retire on the Senate floor on Tuesday, the newspaper reported.

Will Allison, Flake’s campaign spokesman, confirms to CNN that he is not running.

His decision means Flake joins retiring Tennessee Sen. Bob Corker as an outspoken critic of Trump with nothing to lose in the year before 2018’s midterm elections.

Flake’s political fortunes suffered as a result of his long-running feud with Trump — including an anti-Trump tome Flake published over the summer. Private polls conducted by Republican and Democratic groups in Arizona, sources with those groups said, showed him on track to lose badly in next August’s Republican primary to challenger Kelli Ward.

His retirement is a double-edged sword for Trump’s White House: It opens the door for Flake to be replaced with a more supportive Republican. But his seat also now becomes a prime Democratic pick-up opportunity.

And it turns Arizona — once a Republican stronghold but increasingly competitive in recent elections — into perhaps the most important state in the 2018 midterms, with Flake’s seat now open and questions looming about Sen. John McCain’s long-term prognosis as he is treated for brain cancer.

In politics and personality, Trump and Flake have little in common.

Flake, a Mormon from the tiny town of Snowflake, Arizona, is polite and introspective. He journals regularly and, while in the House, regularly emailed his thoughts on travel and policy to a small, private list of family and friends.

He’s long expressed major policy differences with Trump — particularly on trade. In August he called Trump’s decision to withdraw from the Trans-Pacific Partnership “a big mistake which will haunt us for a long time.” He has also defended the North American Free Trade Agreement, warning that its cancellation would badly damage the economies of border states like Arizona.

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