Q: Why Did Richardson Cross the Road?

A: To get superdelegates to the other side.

Two months and dozens of primaries after dropping out of the race, New Mexico Gov. Bill Richardson finally went public with his undying love for Barack Obama. He’ll be in Oregon with Obama today to officially announce his endorsement.

This isn’t exactly a surprise. There have always been rumors that Richardson’s precinct captains told their Iowa supporters to back Obama if Richardson didn’t meet the viability threshold at their caucuses. Earlier this month, just before the Ohio and Texas primaries, Richardson showed up on Face the Nation with a beard and a definitive message: “Whoever has the most delegates after Tuesday, a clear lead, should be, in my judgment, the nominee.” Richardson knew that Obama had the lead going into that Texahio Tuesday, and that he still would coming out of it.

We’re still not sure endorsements matter—Ted Kennedy flubbed miserably—but if they do, then this one might carry some weight. Richardson gained some national recognition when he was running for president, but his lack of star power doomed him. His résumé remains impressive , and he polled reasonably well in Iowa before Iowans decided a caucus threesome of John, Barack, and Hillary was exciting enough.

The significance of the endorsement isn’t what it would have been two months ago. If Richardson made an endorsement pre-Super Tuesday, his support would have been seen as simply a high-profile Latino supporting Obama. But now, Richardson’s a high-profile superdelegate who wants the primary to be over even more than he wants Obama to win. He could have continued to sit on the sidelines until after Pennsylvania’s primary, but he sidled up to Obama now to try to end the race before it hurts the party. When you dovetail his support with it’s-about-time media reports that Clinton’s path to the nomination is blocked off , Richardson knows this could be a clarion call to other superdelegates.

There’s been a smooth, if unimpressive, flow of superdelegates to Obama since Super Tuesday, but Clinton’s victories have forced superdelegates to think twice about crossing the street to hang with the cool kid. Uncommitted superdelegates have spent the last two months nervously looking both ways before they cross. Richardson had the stones to be one of the first to start walking. He won’t be the last.