It's over. No matter what Clinton says tonight, this AP lede marks the beginning of the general election campaign:

WASHINGTON (AP) - Barack Obama effectively clinched the Democratic presidential nomination Tuesday, based on an Associated Press tally of convention delegates, becoming the first black candidate ever to lead his party into a fall campaign for the White House.

Campaigning on an insistent call for change, Obama outlasted former first lady Hillary Rodham Clinton in a historic race that sparked record turnout in primary after primary, yet exposed deep racial divisions within the party.

The AP tally was based on public commitments from delegates as well as more than a dozen private commitments. It also included a minimum number of delegates Obama was guaranteed even if he lost the final two primaries in South Dakota and Montana later in the day.

The 46-year-old first-term senator will face Sen. John McCain of Arizona in the fall campaign to become the 44th president.

Read the full article. It's the first draft summary of a nominating process that is now behind us.

As Josh Orton puts it:

This story is whipping around Blackberries across the country. Hillary's campaign is trying to thread a needle between acknowledging this reality and not "conceding" to try to preserve some sort of leverage with the Obama campaign. But there are a lot of hours between now and the moment Hillary Clinton has to step on stage in New York, during which time more supers will come out for Obama (there's already a flood today and this story gives them more cover) and she'll likely lose two states. The 'leverage' she was hoping to preserve before conceding has started leaking out a large hole at the bottom of the bucket.