Lindsay Graham surprised a lot of us earlier in the week when he said that if Obama persists in releasing Taliban, and presumably al Qaeda, prisoners in contravention of the law then many in the GOP would push for impeachment:

Sen. Lindsey Graham (R-S.C.) warned Wednesday that Republican lawmakers would call for President Obama’s impeachment if he released more prisoners from Guantanamo Bay without congressional approval.

Republicans worry Obama may try to shut down the prison camp unilaterally after congressional opposition has repeatedly stymied efforts to pass legislation to close it.

“It’s going to be impossible for them to flow prisoners out of Gitmo now without a huge backlash,” Graham said. “There will be people on our side calling for his impeachment if he did that.

Coming from Graham and considering the statement was in the context of the statement was a prediction and not a dismissal of the idea this statement seemed extraordinary. But on further examination it is just the latest example of how the Tea Party movement has shifted the GOP caucus, including weak sisters like Graham, further to the right and made them more likely to oppose the increasingly egregious actions of Obama. As the National Journal observed in The Tea Party has already won:

So even if Republicans facing primary challengers from the right are not in real danger, their rivals will keep bringing the heat, scrambling the potential for deals by a Congress already making history for doing so little.

“The tea party has racked up important victories electorally but also ideologically, and that pressure on establishment Republicans will continue,” said James Hartman, a Louisiana-based political consultant advising tea party-backed congressional candidate Rob Maness. “The compromises being blocked are absolutely favorable in terms of public policy. No, we don’t want tax increases. No, we don’t want Obamacare.”

The battle for the heart and soul of the Republican Party expanded in the past week to include challenges against Mississippi Sen. Thad Cochran and Texas Sen. John Cornyn, bringing the total of GOP senators facing primary opponents to seven. All of the incumbents are favored to beat their opponents. But that doesn’t mean they’re free to cut any deals across the aisle; doing so would be risky in a highly polarized political climate that sees compromise as betrayal.

“Members of Congress are risk averse, and if they can avoid getting attention from the bullies, they will,” said Republican consultant John Feehery, a former Capitol Hill staffer.

While the establishment has made a big deal of their antipathy towards the Tea Party and conservatives, the fact is that in the long run we are winning. Unseating guys like Bob Bennett (UT) and defeating Charlie Crist (FL) and David Dewhurst (TX) in primaries were significant events in putting strong conservatives, Lee, Rubio, and Cruz, in the Senate. The fact is, as Erick pointed out a few days ago, time is on our side:

And here is the dirty little secret. The establishment largely has to win every one of their races. The grassroots do not. We just need to add to the ranks of conservatives in the Senate. And we are doing that. The establishment and grassroots are playing two different games. The establishment can pour money in and win in most cases as they have done. But the grassroots can just keep nibbling away.

But more than the inevitability there is the fear. No politician likes a primary challenge and the threat of primary challengers are forcing more and more Republican politicians to act a lot more conservative than they really are. From the Washington Post, How Cornyn, Alexander beat back tea party challenges, and Cochran didn’t:

Sen. John Cornyn (R-Tex.) chose a military metaphor to his approach: “My strategy was the same as Norman Schwarzkopf’s in Desert Storm: overwhelming force. We didn’t want to have a fair fight.”

For Sen. Lamar Alexander (R-Tenn.), the key is a constant presence all over his state. “The most important thing to do is stay connected to the voters,” Alexander said.

After five long years of experimentation, veteran Senate Republicans now say there are a few clear paths for easily beating back a tea party challenge. Sen. Thad Cochran (R-Miss.) took a separate route and now finds himself in a desperate three-week sprint against a GOP state senator, hoping that the Republican establishment will prop him up against an onslaught of money from Washington-based conservative groups.

Cochran was thrown into a June 24 runoff against Chris McDaniel after both men fell short of the 50 percent threshold needed to win a primary in Mississippi. If Cochran loses, it will happen at least in part because of a campaign that bears all the hallmarks of a veteran who had no feel for modern political combat or a full grasp of insurgent challenges to the GOP establishment. He would be the fourth Senate Republican to lose in a primary since 2010.

This is the strategy Graham is following. Even though he is the most liberal member of the South Carolina congressional delegation according to the Heritage Action Scorecard, his is spending a lot of money on his election and trying to at least appear to be more in sync with his constituents. We know with mathematical certainty that Graham is going to be re-elected and we need to hold him to his campaign rhetoric when he returns to the Senate.