President Donald Trump appears to endorse Kelli Ward in tweet bashing Sen. Jeff Flake

President Donald Trump landed a long-anticipated blow to Sen. Jeff Flake of Arizona early Thursday, seemingly endorsing his Republican primary opponent in a Twitter message.

In a tweet posted at 3:56 a.m. Arizona time, Trump said: "Great to see that Dr. Kelli Ward is running against Flake Jeff Flake, who is WEAK on borders, crime and a non-factor in Senate. He's toxic!"

The social-media attack on Flake, R-Ariz., who recently wrote a book critical of the Republican Party's embrace of Trump's politics, left Ward, the former state senator from Lake Havasu City, jubilant. And it left Flake's fellow Republicans scrambling to defend him from the president of their own party.

"Jeff Flake is an excellent Senator and a tireless advocate for Arizona and our nation," Senate Majority Leader Mitch McConnell, R-Ky., said Thursday afternoon in a brief written statement. "He has my full support."

Sen. Bob Corker, R-Tenn., chairman of the Senate Foreign Relations Committee on which Flake sits, on Thursday praised Flake as "one of the finest human beings I've ever met."

"The White House would be well-served to embrace the character, the substance, of someone like Senator Flake," Corker said. "He's one of the finest people I serve with. He's got a conscience. He is a real conservative. ... I hope for the good of our country he is someone who will be serving after 2018, and I'm thankful to know him."

But Flake has been on Trump's radar for a long time, and Flake likely exacerbated the already negative relationship with the Aug. 1 publication of his anti-Trump book, Conscience of a Conservative: A Rejection of Destructive Politics and a Return to Principle.

First elected to the Senate in 2012 and up for re-election in 2018, Flake was one of Trump’s most vocal Republican critics during the presidential campaign, refusing to endorse or vote for him. He recently published a book that further antagonized the president by criticizing the new influence of pro-Trump populists, protectionists and conspiracy theorists.

Ward, meanwhile, has been a vocal supporter of Trump's agenda and at times publicly parroted some of his controversial statements, including blaming "both sides" for the recent violence in Charlottesville, Virginia.

A buoyant Ward appeared on Phoenix radio station KFYI-AM (550) shortly after 6:30 a.m.Thursday.

"It's a pretty darn great morning," she said, adding that Trump's tweet of support was a sign of escalating momentum for her campaign against Flake.

"The president is exactly right: Jeff Flake is weak on the border," Ward said on KFYI. "He's an open-borders globalist. He has embraced the term 'globalist' himself."

Ward said that she and "Team Ward" will be out "in full force" Tuesday at Trump's rally at the downtown Phoenix Convention Center. She stopped short of saying whether she would be speaking at the event, only saying "there's a lot of discussion going on right now."

The National Republican Senatorial Committee, the arm of the Republican Party that works to elect GOP senators, is sticking by the incumbent Flake.

"The NRSC unequivocally supports Senator Flake in his reelection bid," said Sen. Cory Gardner, R-Colo., the NRSC chairman.

If Trump has, in fact, landed on Ward as his favored challenger to Flake, it would set up a proxy war of sorts between factions within the Arizona Republican Party for next year's Senate nomination.

Will Allison, a spokesman for Flake’s 2018 re-election campaign, accused Trump and Ward, two Washington outsiders, of making a new kind of inside-Washington agreement.

"You don't serve Arizona by cutting backroom deals in Washington, D.C.,” Allison said in a written statement provided to The Arizona Republic. “That's why Senator Flake will always fight for the people of our state.”

Ward last year challenged McCain in the GOP primary but lost. She earned nearly 40 percent of the vote to McCain's 51 percent in a four-way race.

Not long after her defeat, she re-launched her campaign for the 2018 primary against Flake.

Ward recently received national attention by saying McCain, who is undergoing treatment for brain cancer, should step down so that Gov. Doug Ducey could appoint a new Republican senator to replace him. And she said she thought she should be considered for the job.

In a Thursday morning tweet, McCain, who also has long been at odds with Trump, defended his ally Flake as "a principled legislator" who does what's right for the people of Arizona.

"Our state needs his leadership now more than ever," McCain said.

Trump’s apparent endorsement of Ward comes two days after a news conference in which the president again blamed “both sides” for violence at a Saturday rally by white supremacists and neo-Nazis. Three people died, including a woman killed after a car rammed into a crowd of counter-protesters.

Ward voiced agreement with Trump's casting blame on both sides, saying in a message on Twitter "I agree - stop the hate, violence & rhetoric on both sides - we need to stand together as Americans!" As part of her message she quoted Trump's tweet on the matter. 

Trump's shout-out to Ward gives her a clear boost over possible rival Robert Graham, a former state GOP chairman who has been seen as a potential entrant into the Senate race. Jeff DeWit, the Arizona state treasurer who is close to Trump, also has frequently been mentioned as a possible candidate but this week made public comments that indicated he's not that interested in the Senate job.

Former Rep. Matt Salmon, R-Ariz., came up briefly Thursday as the favorite of some in Trump's orbit but he quickly confirmed that he instead will keep his post-Congress job at Arizona State University.

The president apparently decided to say something nice about Ward without giving his aides a heads up. Also, he may have been channeling former Rep. J.D. Hayworth, R-Ariz., who appeared on the Fox News Channel shortly before Trump tweeted.

Hayworth, whose 2010 primary challenge for the Senate was crushed by McCain, praised Ward and blasted Flake as "toxic," the same word that appeared in Trump's subsequent anti-Flake tweet.

"Dr. Kelli Ward is out working hard," Hayworth said on the early-morning "FOX & Friends" program. "... She gave John McCain a great race in the primary of 2016; in fact, performed better than I did in 2010. She's got the momentum, she's gaining some of the money, keep your eyes on Kelli Ward."

Hayworth, who served six terms in Congress before his 2006 ouster by Democrat Harry Mitchell, further accused Flake of doing his best "to be obnoxious, to be the smirking senator that he is really known to be."

This week's Republican Senate primary in Alabama gave a glimpse at Trump's influence in GOP races around the country. The president endorsed incumbent Sen. Luther Strange, who on Tuesday finished second behind Roy Moore, a former Alabama Supreme Court chief justice. But Strange's performance was good enough for him to proceed to a runoff, and some observers say he might not have made it to the next round without Trump's help.

Nowicki is The Republic's national political reporter. Follow him on Twitter, @dannowicki.

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