Several Republican senators are in danger of losing primary battles -- and it could signal where the party is going in the age of Trump

Three Republican senators appear to be at risk of losing primary battles to challengers, a feat that has only been pulled off five times since 1994.

Those who appear at risk of losing their seats to right-wing challengers included Sens. Luther Strange of Alabama — who will face Alabama Supreme Court Chief Justice Roy Moore in a run-off election next week — Jeff Flake of Arizona, and Dean Heller of Nevada.

The trio of Republican senators have fared poorly in recent polls testing them against their challengers. For Strange, who was appointed to the seat held by Attorney General Jeff Sessions, his polling deficit to Moore exceeds eight points, according to the RealClearPolitics average.

Unlike Flake and Heller, however, Strange has had Trump’s support throughout the election, even while his opponent has received backing from many pro-Trump corners of the party. Breitbart News, which is once again run by former White House chief strategist Steve Bannon, has promoted Moore’s candidacy heavily on its platform.

Pro-Moore forces have sought to tie Strange to the Washington, DC, establishment, linking him closely to Senate Majority Leader Mitch McConnell.

Trump reaffirmed his support for Strange in a tweet over the weekend.

“I will be in Huntsville, Alabama, on Saturday night to support Luther Strange for Senate,” Trump tweeted this weekend, announcing he will make a stop in Alabama ahead of next week’s runoff election. “‘Big Luther’ is a great guy who gets things done!”

It’s quite a different tale for the other two Republican incumbents.

Flake, the Arizona Republican who has been one of the most vocal Trump critics in the GOP, trailed primary challenger Kelli Ward, a former state Senator, by 26 points in a late August JMC Analytics poll. Flake, however, could see his stock boosted by the addition of other primary opponents into the field. A series of other challengers is considering getting into the race, which could cut down on the portion of the anti-incumbent support that Ward has received.

Earlier this summer, in his book, “Conscience of a Conservative,” Flake wrote that his party was in “denial” about Trump, describing an executive branch “in chaos” and a president who has “seeming affection for strongmen and authoritarians.”

Trump, though he has not endorsed Ward and recently spoke with other potential primary challengers before a rally he held in Arizona, tweeted his support for Ward’s campaign last month.

“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,” Trump wrote. “He’s toxic!”

Trump has promised to spend as much as $US10 million to oust Flake. One of Trump’s top donors, the billionaire hedge fund manager Robert Mercer, has donated $US300,000 to a pro-Ward super PAC, Politico reported.

Heller, the only Republican running for reelection in 2018 in a state that Democratic presidential nominee Hillary Clinton won in last fall’s election, finds himself trailing his primary challenger, Danny Tarkanian, by eight points in a late August JMC Analytics poll. Tarkanian is the son of legendary University of Nevada-Las Vegas basketball coach Jerry Tarkanian.

Though Trump has not outwardly advocated for Heller’s defeat, a pro-Trump nonprofit launched a $US1 million anti-Heller ad campaign in Nevada (with the White House’s blessing) for his refusal to back the original Senate healthcare bill. The ads were quickly pulled after top Senate Republicans, including McConnell, voiced opposition to the campaign against Heller.

During a July healthcare roundtable with Republican senators, Trump suggested that Heller would eventually vote for the Senate’s bill and joked on camera, “Look, he wants to remain a senator, doesn’t he?”

The last Republican senator to succumb to a primary challenge was Sen. Richard Lugar of Indiana in 2012, who lost to Indiana treasurer Richard Mourdock. Mourdock lost the general election race to Democrat Joe Donnelly, who pulled off an upset in a heavily Republican state partially due to Mourdock’s comment during a debate that a pregnancy resulting from rape was “something God intended.”

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