Sarah Palin just endorsed a primary challenger to one of the most vulnerable Republican senators

sarah palin AP/Susan Walsh

Sarah Palin endorsed a primary challenger to a vulnerable Senate Republican on Thursday, setting the stage for what could be a contentious midterm election in Nevada.

The former vice presidential candidate announced through Breitbart her support for businessman Danny Tarkanian in his bid to unseat Dean Heller in 2018.

"Danny Tarkanian is a conservative outsider who will support the ‘America First’ policies our nation needs to survive and thrive, including building the border wall, ending sanctuary cities, and finally repealing Obamacare,” Palin said in her announcement.

Heller has been a target for far-right conservatives since he denounced a Republican bill that would have repealed the Affordable Care Act. President Donald Trump notably threatened to support a primary challenger to Heller if he didn't support the legislation, and Heller ultimately voted in favor of the bill.

Heller was one of two swing-state Republicans Trump has threatened politically — the president has also openly courted primary challengers to Arizona's Jeff Flake, who he has criticized for opposing his plan to build a border along the Mexican border.

Tarkanian, the son of legendary University of Nevada-Las Vegas basketball coach Jerry Tarkanian, has unsuccessfully run for statewide and national office five times since 2004.

"I thank Governor Palin for her endorsement and appreciate the confidence she has shown in our campaign," Tarkanian told Breitbart. "I will hold Dean Heller accountable for turning his back on Nevadans by voting against the repeal of Obamacare and helping Hillary Clinton win Nevada by attacking Donald Trump over and over again."

Democrats view Nevada as one of their best chances to steal a seat in next year's midterms. Their leading challenger for Heller's seat, Rep. Jacky Rosen, defeated Tarkanian in the 2016 election for Nevada's 3rd Congressional District.

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