Nationalist firebrand Steve Bannon is mobilizing a revolt against Senate Majority Leader Mitch McConnell, even if it costs President Trump some of his most loyal foot soldiers on Capitol Hill.

Bannon, Trump's former chief strategist, is raising resources and recruiting primary challengers to take on Republicans who vote for the president's legislative agenda more than 90 percent of the time — some more than 95 percent of the time.

Their sin isn't insufficient fealty to Trump or even ideological differences, but rather supporting McConnell, R-Ky., for majority leader.

Bannon, now back at the helm of Breitbart News, loathes the Kentucky Republican. Bannon is willing to jettison reliable conservative votes for Trump's program if he can replace them with senators who are guaranteed to oppose McConnell when he next stands for election as majority leader after the midterm elections.

"He is asking questions of these guys running in 2018: Will you, or will you not vote for Mitch McConnell for majority leader? The correct answer is no," said Ned Ryun, founder and CEO of the conservative group American Majority and has discussed the matter with Bannon.

"Bannon hates McConnell," added a Republican donor who met with Bannon recently to listen to his 2018 pitch, and requested anonymity in order to discuss a private conversation.

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Bannon's top targets include Sens. John Barrasso of Wyoming, a member of McConnell's leadership team; Deb Fischer of Nebraska; and Roger Wicker of Mississippi. Barrasso and Wicker vote with Trump 96 percent of the time, respectively. Fischer sides with the president 92 percent of time, according to an tracking from FiveThirtyEight.

And even occasional Trump critics like Sens. Jeff Flake, R-Ariz., and Dean Heller, R-Nev., two other Bannon targets, vote with the president 92 percent of the time and 90 percent of the time, respectively.

Meanwhile, in the just concluded GOP primary runoff in the Alabama special election, the Bannon-backed candidate, retired judge Roy Moore, pledged to oppose the legislation Trump was backing to repeal and replace Obamacare. McConnell's candidate, appointed Sen. Luther Strange, supported it.

A spokesman for Bannon did not respond to a set of questions submitted via email.

But conservative insurgents that have talked 2018 strategy with Trump's former presidential campaign CEO say that he holds McConnell responsible for the collapse of Senate legislation to repeal Obamacare and inaction on other Trump priorities. The Senate health care bill died — twice — because 50 Republican votes failed to materialize.

McConnell's critics on the Right, like Bannon, believe the majority leader could have applied more pressure to his rank-and file members if he really wanted to repeal former President Barack Obama's health care law and help Trump deliver a key campaign promise. He simply didn't want to, they contend, and it's a major frustration.

"When leadership wants something to happen, arms are twisted, committee assignments are threatened," Ryun said. "If these guys had been on the same page and were all for pushing Trump's agenda, we would have done something by now on healthcare, tax reform and infrastructure."

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Bannon's Republican critics describe his effort as part naked power play and part vengeful grudge match.

The wealthy, politically savvy former investor wants to transform the GOP from home for intellectual and market-driven conservatism, into a populist haven for economic and cultural nationalism.

McConnell, a pragmatic old-guard conservative, is responsible for sinking several GOP primary challengers over the past five years that would have pushed the party in Bannon's direction.

The infighting could cost the GOP seats in the midterm, warn some Republicans, as resources and attacks that could be focused on Democrats are instead are deployed inward, diminishing voters' overall image of the party and discouraging GOP turnout.

"He's a bright guy, but I don't know where he's headed on this. There are more important people to fight," said a House Republican who professes to like Bannon personally and shares his frustration with the Senate. "He needs to be careful about starting something when we're all on the same team."

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