Breaking up is hard to do, except in politics.

Competing with HillaryCare 2.0 is nothing like running against the RockStar. This race has taken some turns that I could have never expected, and this could yet be another one:

… Yes, yes, I know. Gore has said he won’t endorse. He’s happily retired from politics now, a senior statesman, a big-shot investor. He’s won an Oscar and a Nobel. The cause he crusaded for has become central to the public conversation in a way even he could never have imagined.

All of these are good reasons to stay out of the fray. But they’re equally good reasons to jump into it. What would be the risk? There’s no chance that his endorsement would be followed by an embarrassing Dean-like collapse; Obama has already notched wins. Climate change won’t suddenly disappear from the agenda if he loses. And nobody’s going to take away the golden statuette.

On the other hand, Obama is now close enough to a big win that Gore’s endorsement could easily put him over the top. Gore is beloved among Democratic primary voters. His staunch denials have been unusually effective in tamping down speculation that he’ll endorse, so an announcement would be earthshaking and guaranteed to dominate the airwaves until the February 5 primaries. Take Tennessee, Gore’s home state, which could wind up making the difference. Democratic polling there is somewhat sparse, especially that done after John Edwards’s withdrawal. But Tennessee looks to be a state in which Clinton currently holds a lead-that is, unless a certain favorite son were to endorse her opponent.

Gore has already seen one presidency (his own) slip away over a handful of votes. He must have pondered how it would feel to play kingmaker and shore up someone else’s path to the White House.

A well-connected Tennesseean told me two things today that got me thinking about this. The first is that Obama and Gore have been speaking regularly, about every two weeks or so. The second is that, despite this, and despite Tennessee’s primary on Tuesday, Obama has not visited the state since June. It may be simply that he does not plan on competing there. Or it may be that he’s been waiting for a special occasion.