On Sunday, Senator Joe Lieberman infuriated Democrats by announcing that he would vote against the latest compromise health care legislation, despite the fact that during the delicate crafting of the compromise he had told them he would support it. His stated reason? The compromise would allow people starting at age 55 to purchase health insurance from Medicare, which Lieberman said he could not support.

But a video turned up of Lieberman not only endorsing expanding Medicare to people over the age of 50, but trying to take credit for it as his own idea: “What I was proposing was that they have an option to buy into Medicare early.”

When confronted with the video, taken only three months ago, Lieberman replied that he did not dispute that he once supported the idea but said he did not recall having done so, or the context, until Mr. Reid’s office confronted him about it.

So why did Lieberman do such a complete flip-flop? According to the NY Times:

Mr. Lieberman could not be happier. He is right where he wants to be — at the center of the political aisle, the center of the Democrats’ efforts to win 60 votes for their sweeping health care legislation. For the moment, he is at the center of everything — and he loves it.

Indeed, in an interview yesterday, Lieberman flashed a broad grin, saying “My wife said to me, ‘Why do you always end up being the point person here?’” It is worth noting that his wife is a former pharmaceutical company executive. And during his 2006 Senate reelection campaign, Lieberman received the second highest amount of campaign contributions from the health insurance industry in the Senate.