Erick Erickson runs the conservative blog (via CNN) (CNN)

“I can give no absolution for what you may be about to do,” wrote Erickson, who opposed the version of Boehner’s plan that never secured a expected vote on Thursday night because it would have been defeated. “I can offer no alternatives.”

Who is Erickson, and why does his opinion matter to House Republicans?

Well, it depends who you ask. GOP leadership staffers grumble that he’s a nag who gets tons of media attention but has little real power. Allies say he’s a powerful voice for conservatives, with a grassroots network that can launch a candidate out of obscurity.

Either way, nobody was willing to talk on the record about the powerful blogger. The Fix reached out to Erickson for comment, but he was unavailable at press time.

RedState’s traffic numbers aren’t huge — the site hosts about 178,000 unique visitors and one million page views monthly , according to comScore. But through a mix of incendiary posts, canny self-promotion (he has 24, 540 Twitter followers) and endorsement of conservative primary candidates, the 36-year-old former city councilman’s has made himself something of a conservative powerbroker. Rush Limbaugh, with his millions of listeners, often turns to Erickson for inspiration. At least one congressman — rising tea party star Rep. Joe Walsh (R-Ill.) — says he has asked Erickson for advice.

Even if he’s widely read among Republicans, Hill Republicans argue that Erickson’s stances are too predictable to make him a serious GOP force.

“He certainly doesn't have the influence of the Wall Street Journal, the Weekly Standard, [Web site] Hot Air or the National Review,” said a Republican leadership aide. “He would have more influence if he was a little more strategic.”

But others counter that Erickson helped propel conservatives into office in the 2010 elections — including now South Carolina Gov. Nikki Haley (R). When former Alaska governor Sarah Palin endorsed Haley, Erickson was on the stage with them. It’s that power that gives Erickson’s policy positions weight.

“Erick's impact was real in gubernatorial races. And not only was it real, it was positive,” said Nick Ayers, who led the Republican Governors Association for the past two cycles and now runs Tim Pawlenty’s (R) 2012 presidential campaign. “While he's typically tough on national political committees, I found that by simply reaching out, making clear your goals and plans, he was often a team player and brought energy, excitement, and money to candidates he would get behind.”

Rick Wilson, a strategist for RedState-endorsed 2012 Florida Senate candidate Adam Hasner says Erickson’s backing “absolutely helps, absolutely matters,” calling the site “one of the new centers in the conservative movement.”

Erickson’s picks on the primary playing field haven’t always panned out. But every would-be kingmaker has a mixed record. Just check out our map of Palin’s 2010 endorsement record.

On the winning sid e of the ledger, Erickson did back a number of candidates in competitive primaries who are now in office, including Rep. Marlin Stutzman (R-Ind.) (who lost a Senate primary but got into the House), Rep. Dan Benishek (R-Mich.), Virginia Attorney General Ken Cuccinelli, Sen. Marco Rubio (R-Fla.), and Sen. Rand Paul (R-Ky.).

In 2010, Erickson also supported plenty of Republican primary failures: including Danny Tarkanian in the Nevada Senate primary; Chuck DeVore in the California Senate primary; Pamela Gorman in Arizona’s 3rd district; Rick Barber in Alabama’s 2nd district; Karen Handel in the Georgia gubernatorial race; and Rep. Todd Tiahrt in the Kansas Senate primary.

Erickson also endorsed a number of candidates who went on to lose key 2010 general elections that could have possibly gone Republican if the nominee had been different. They included Ken Buck in the Colorado Senate primary; Chris Hackett in a Pennsylvania House primary; and most famously, Christine O’Donnell in Delaware.

Erickson can argue that even when his preferred candidates lose, he succeeded in forcing Republican candidates to the right. The morning after a Democrat won a seat in upstate New York thanks to a conservative primary upset, Erickson declared the result “a huge win for conservatives.”

That attitude is part of what bothers Republicans on Capitol Hill.

“He might have helped some candidates get through primaries, but I think he may hurt more than he helped,” said a House Republican aide. “I don’t think he can win primaries, but he certainly can take down a primary candidate. It’s being a bully, essentially.”

But if he’s a bully, he’s one that congressmen worried about primary challenges obviously listen to — as shown by the revolt against Boehner on Thursday night.

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