Several key Capitol Hill Republicans stood defiant yesterday against the types of changes to U.S. global warming policy spelled out earlier this week by presumptive Republican presidential nominee John McCain ...

"I'm going to vote for McCain this year for president, but if he offers that bill I'll vote against it and work against it," pledged Rep. Joe Barton (R-Texas), the top Republican on the House Energy and Commerce Committee ...

Sen. George Voinovich (R-Ohio), who would likely become the lead Republican on the Senate Environment Committee next year if McCain wins the presidency, said he wanted to work on a different type of climate plan that focused first on incentives for new energy technologies.

"We both agree there's a problem," Voinovich said. "We have a difference of opinion about how to solve the problem."

Retiring Sen. Pete Domenici (R-N.M.), the ranking member of the Senate Energy and Natural Resources Committee ... "I'm not for that," Domenici said. "I respect [McCain] greatly. But I think before we're finished, there'll be an awful lot of reality added to this."

That's a pretty pathetic response, especially when you consider that McCain's plan is already too watered down to solve the climate problem. Still, it can't be considered a big surprise, given that only 27 percent of conservatives say human emissions are warming the earth.

Interestingly, there is at least one conservative who understands the central flaw in McCain's plan:

Sen. Bob Corker (R-Tenn.), for example, said he wasn't so sure McCain got it right in calling for the unlimited use of domestic and international offset projects for industry compliance in a cap-and-trade system. "That's something that's very poor public policy and hopefully he'll evolve on that," he said.

(Note to Corker: Conservatives don't believe in evolution!)

On the other hand, even a conservative from the state most obviously suffering the consequences of global warming endorses a strategy that would gut any climate bill:

Alaska Sen. Lisa Murkowski challenged McCain to reverse his position against a "safety valve" that puts an absolute ceiling on the price of emissions.

(Note to Murkowski: A safety valve undermines the whole point of cap-and-trade.)

Even a couple of sort of moderate conservatives won't go as far as McCain's lame bill:

Sen. Lamar Alexander (R-Tenn.) said he did not support the economy-wide climate proposal McCain suggested earlier this week ...

Sen. Judd Gregg (R-N.H.), one of the six Republicans who twice voted for McCain's original climate bill, echoed that assessment. "These are starting points," he said. "I don't see them as ending points."

Yes, my fellow Americans, conservatives remain the single biggest obstacle to avoiding catastrophic global warming.

This post was created for ClimateProgress.org, a project of the Center for American Progress Action Fund.