Last week he was “quietly campaigning” against it, today he’s suddenly seen the light. Why the change? Well, for starters, DeMint now thinks he has enough votes to pass the resolution in tomorrow’s caucus meeting. The last thing McConnell needs at the start of a new term is an embarrassing defeat, especially with Tom Coburn hint-hinting that earmark supporters should be primaried and with rumors forever swirling that DeMint might challenge McConnell for majority leader. (Indeed, DeMint’s already rushed out a statement congratulating McConnell for his “bold leadership.”)

Beyond that, though, I think his hand was forced this weekend when not only did Boehner and Cantor come out in support of an earmark ban but even Obama talked up earmark reform in his weekly address. Siding against the new Speaker and his class of tea partiers would have been tough enough for McConnell, but ending up on the wrong side of the issue from The One? Unthinkable. His reelection bid would have been over before it began. The key bit from his floor speech, via the Standard:

Republicans in and out of Washington have argued strenuously for two years that spending and debt are at crisis levels. And we have demonstrated our seriousness about cutting spending and reining in government. Every Republican on the Senate Appropriations Committee, for instance, voted against every appropriations bill in committee this year because they simply cost too much. Most included funding for projects in our home states. We voted against them anyway.

Banning earmarks is another small but important symbolic step we can take to show that we’re serious, another step on the way to serious and sustained cuts in spending and to the debt.

Earlier this month voters across the country said they are counting on Republicans to make tough decisions. They gave us a second chance. With this decision, I’m telling them that they were right to put their trust in us. And it’s my fervent hope that it will help demonstrate to the American people in some way just how serious Republicans are about not letting them down.

Knowing that his floor speech today would get lots of media play, he also made sure to remind Kentucky voters of some of the choicer cuts of pork he’s provided for them over the years. As for tomorrow’s vote, which now seems like a fait accompli, I heartily endorse this suggestion from incoming tea party Sen. Mike Lee: End the secret ballot and put everyone in the caucus on the record. If they had done that on the vote to strip Murkowski of her Energy committee leadership position, the outcome might have been different and who knows what it would have meant for the Alaska Senate race. If the “new GOP” is serious about accountability, there’s no reason not to make the vote public. The only thing secrecy achieves is protecting incumbents from primary voters by absolving them of responsibility for their votes.

I’ll leave you with this from AmSpec’s Philip Klein, summarizing my own worries about the recent obsession with earmarks: “While I agree with this as far as it goes — and support a ban on earmarks — I also think that the overemphasis on earmarks has distracted attention from the much more important issue of how to deal with the entitlement spending mess. Republican candidates were able to run this year on vague promises of cutting wasteful spending. When pressed on ideas to combat the looming entitlement crisis, they’d often talk about how we needed to take on earmarks and pork barrel spending first. What I fear is that if the GOP eliminates earmarks, it will cite that as progress in reducing the debt when running for reelection, once again trying to deflect attention from entitlements.” Click the image to watch.