SOME PEOPLE ARE VERY HARD TO PLEASE…. The competing contingents in the Senate Democratic caucus continue to move towards a compromise on the public option. Whether the deal will come together, and whether it can garner the support of the entire 60-member caucus, remains to be seen.

But while those talks continue, everyone is also keeping an eye on the Republicans from Maine — Sens. Olympia Snowe and Susan Collins — whose position on health care reform will be that much more significant if conservative Dems like Ben Nelson balk. Any chance they might also like the compromise away from the public option? In Snowe’s case, probably not. (thanks to reader K.Z. for the tip)

Sen. Olympia Snowe (R-ME) says a Medicare buy-in approach will be a hard sell with her. She told reporters this afternoon that she’s not inclined to support the idea, currently being discussed by liberal and conservative Democrats seeking a compromise on the public option.

“We looked at it…we evaluated that, because it’s an attractive approach. This has appeal…but we examined that issue this summer and a number of issues cropped up.”

She’s expressed her doubts to Senate Majority Leader Harry Reid. “I told him I have concerns,” she said. “The Medicare buy in is problematic.”

A reporter asked if that meant she’s not inclined to support the idea. “Correct,” she said.

She’s also against a modest increase in Medicaid eligibility expansion.

If Snowe is prepared to block a vote on health care reform, Collins will likely be an even tougher sell. And if the Mainers are out, we’re right back to needing every vote in the Democratic caucus, just to overcome a Republican filibuster.

Update: Lieberman is making encouraging noises about the public-option-less compromise.

Steve Benen

Follow Steve on Twitter @stevebenen. Steve Benen is a producer at MSNBC's The Rachel Maddow Show. He was the principal contributor to the Washington Monthly's Political Animal blog from August 2008 until January 2012.