(REUTERS) Former U.S. vice presidential candidate Sarah Palin vowed on Sunday to help unseat Paul Ryan, the top Republican in the House of Representatives, because of the his refusal to endorse presumptive Republican nominee Donald Trump.

Palin, the former Alaska governor and Trump supporter, endorsed conservative businessman Paul Nehlen, who is challenging Ryan, the House speaker, for his congressional seat in the Wisconsin Republican nominating contest on Aug. 9.

“I will do whatever I can for Paul Nehlen,” Palin said in an interview with CNN. “This man is a hardworking guy, so in touch with the people.”

Though Ryan is heavily favored to win the primary race against Nehlen, Palin predicted an upset in a race she said would shock Washington’s political class.

Read the rest of the story at Reuters.com.