Lindsey Graham — an original cosponsor of the Senate climate bill — has been backing away from that bill for a while. Now, according to CongressDaily, he’s gone entirely:

Sen. Lindsey Graham, R-S.C., today said he would vote against a climate change strategy he helped develop with Sens. John Kerry, D-Mass., and Joe Lieberman, D-Conn., citing new changes that further restrict offshore oil and gas drilling and the bill’s impact on the transportation sector.

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Yes, you read that right: He says he’s bailing from the bill because, in the wake of one of the greatest offshore oil drilling disasters of all time, a bill devoted to reducing climate pollution does not expand offshore oil drilling enough. Such is the Bizarro World of the U.S. Senate.

Graham offers some other justifications for bailing, but as Brad says, they are transparently ridiculous — mostly objecting to provisions of the bill that he was instrumental in shaping. He’s retreating to the now-familiar Republican position of “we need to start over,” which is their way of opposing everything without looking totally nihilistic. He’s also saying some borderline-denialist (but mostly just incoherent) things about climate change, as Kate Sheppard details.

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Basically, the base won. Graham was under the impression, shared by some his older mentors, that Republicans are still the party of business. He thought if he rode in, watered down the bill to make it friendlier to industry, and garnered support from oil companies and manufacturers, he would be hailed as a hero. He hasn’t internalized the fact that the crazies have completely taken over the Republican Party. But they made their will known in no uncertain terms.

So, the loss of drilling means the loss of Graham (and probably Sen. Mary Landrieu, Democrat of Louisiana). Are there other Republicans that could fill the gap? Theoretically, yes: Olympia Snowe (Maine), Susan Collins (Maine), Scott Brown (Mass.), George LeMieux (Fla.), maybe even George Voinovich (Ohio) or Richard Lugar (Ind.).

As with all things congressional, however, the primary effect will be optical. This will further convince Democratic “centrists” (read: craven, ass-covering cowards) that the bill doesn’t have a chance, which makes them more likely to push Senate Majority Leader Harry Reid (D-Nev.) to do an energy-only bill.

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So the climate bill’s already slim chances are now considerably slimmer. But the basic calculus hasn’t changed: If Obama goes all-out after a bill, it could happen. If he doesn’t, it can’t.