Story highlights Wisconsin businessman Paul Nehlen is challenging Rep. Paul Ryan in the Republican primary for his House seat

Nehlen recently got high-profile support of conservative activists like Sarah Palin and Michelle Malkin

Washington (CNN) Wisconsin businessman Paul Nehlen is hoping to be the giant-killer of the 2016 cycle, delivering what would be a stunning blow on par with the surprise primary knockout of Eric Cantor in 2014, but he's got a steep hill to climb to come close to unseating highly popular House Speaker Paul Ryan.

Nehlen is a Wisconsin executive who touts his work bringing jobs back to the United States from Mexico and Canada, a key asset in the manufacturing-heavy Wisconsin district that Ryan represents. And he's gotten the highly vocal support of conservative activists like Sarah Palin and Michelle Malkin.

But it still appears to be a steep climb for anyone looking to unseat Ryan, who is highly popular in Wisconsin and bested his last primary challenger 94%-6% in 2014.

But Palin promised she would get on board any effort to topple Ryan after he expressed his hesitation with presumptive Republican nominee Donald Trump last week. Palin, who has been a vociferous surrogate for Trump and mentioned as a possible running mate, promised that Ryan would be "Cantored" by Nehlen.

"His political career is over but for a miracle because he has so disrespected the will of the people," Palin told CNN's Jake Tapper on "State of the Union" on Sunday.

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