Republican Sen. Jeff Flake of Arizona won’t run for re-election

WASHINGTON — Republican Sen. Jeff Flake of Arizona, who has sparred frequently with President Donald Trump, will not run for re-election, he said Tuesday as part of a blistering floor speech bemoaning the changing tenor of politics in the United States.

“If I have been critical, it not because I relish criticizing the behavior of the President of the United States,” Flake said. “If I have been critical, it is because I believe that it is my obligation to do so, as a matter of duty and conscience.

“The notion that one should stay silent as the norms and values that keep America strong are undermined and as the alliances and agreements that ensure the stability of the entire world are routinely threatened by the level of thought that goes into 140 characters — the notion that one should say and do nothing in the face of such mercurial behavior is ahistoric and, I believe, profoundly misguided.”

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 August’s Republican primary┬áto 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’s decision opens the door for Ward, a conservative former state senator who many Arizona Republicans see as a controversial and problematic general election candidate.

But now that the seat is open, others, including state treasurer Jeff DeWit, the former Trump campaign chief operating officer, as well as several current and former members of Congress could consider entering the primary.

The winner is likely to face Democratic Rep. Kyrsten Sinema.

Flake’s congressional career came full circle. He began in the House in 2001 as an outsider raging against earmarks.

By the time he launched his Senate campaign in 2012, he was a favorite of conservative groups such as the Club for Growth, which had grown in power and influence on Capitol Hill.

Now, Flake is again on the outs, with Trump’s populist policies taking hold with Republican voters.