Obama's big speech today on race, which is set to start within minutes, grew from his sense that he'd failed to adequately explain his relationship to Jeremiah Wright:

After removing Mr. Wright from a religious advisory committee on his campaign on Friday, Mr. Obama concluded over the weekend that he had not sufficiently explained his association with the pastor. He told several aides he was worried that if voters did not hear directly from him — in the setting of a major speech — doubts and questions about him might grow.

There's an irony here worth noting -- or a potential irony, anyway. Even without the latest Wright controversy, there had already been plenty of questions simmering about Obama's race and religion -- witness the Muslim smear that won't die, for example. If Obama's speech today is a success, it could put such questions to rest and indeed give a deeper historical dimension to his candidacy than it already has.

Should that happen, it will be worth pondering that it might not have happened if the controversy over Wright hadn't forced Obama to shove his chips onto something as ambitious and risky as he's about to attempt today. So it's not impossible to imagine that the Wright controversy, as damaging as it now seems, could conceivably prove to be a key turning point in his favor.

Stranger things have happened in politics.