Here are the stats from Puerto Rico, with 99% of precincts reporting:

• Hillary Clinton leads 68%-32%, with a 140,000 lead in the raw popular vote total.

• For the territory's 55 pledged delegates, Clinton will get 38 to Barack Obama's 17. While a +21 take from a single contest might normally be impressive, Obama still leads by over 150 total delegates.

• Turnout was radically lower than anybody had predicted. A total of 380,000 ballots were cast, making up only a little over 16% of the island's voters -- well short of the 900,000 that both campaigns had once thought was a reasonable estimate.

In short, Hillary Clinton's big win today has not changed the fundamental delegate math, with Obama still likely to clinch the nomination later this week. As for the popular vote metric, Clinton will only be able to claim such an advantage if the Michigan primary is factored in to give her nearly 330,000 extra votes, and crediting Obama none of the "Uncommitted" votes that his supporters cast in that primary.

In what might be the last bit of even halfway-decent news for Hillary Clinton during this primary season, the major news organizations are all reporting that she has won the Puerto Rico primary by a very wide margin. No results are in yet, but initial exit poll results indicate her win could be by more than two to one.

However, this outcome is unlikely to really help her win the nomination. Although it might bolster her popular vote arguments, Puerto Rico is not a state and thus can't actually vote for president in the general election -- meaning that this result really has no bearing on the question of electability. And with only 55 total pledged delegates up for grabs here, even a landslide would hardly make a dent in Barack Obama's delegate lead.

Late Update: With 22% of precincts reporting, Hillary leads 67%-33%. Turnout has been very light, coming in steadily at about 15% of registered voters for the precincts that have come in. Should all these trends hold up, Hillary should get roughly a +18 delegate take from the territory, and about +100,000 on the popular vote.

Late Update: With 72% reporting, Hillary leads 68%-32%, with a raw vote lead of about 90,000 votes. If this holds up in the remaining precincts, her popular vote edge would be +130,000 for the territory.

Although all analysts give Hillary Clinton long odds to win the nomination, her major union backers and other big donors clearly haven't given up. The American Leadership Project, the pro-Hillary 527 group, is running a new pair of ads in the upcoming contests of Puerto Rico, where she's favored, and Montana, where Obama is ahead.

Here's the Montana spot, promising that Hillary will help middle-class families and end tax breaks for oil companies:

And here's the Puerto Rico ad, centering around health care:

Barack Obama has now publicly responded to the controversy surrounding Hillary Clinton's reference to the assassination of Bobby Kennedy, saying that he accepts Hillary's explanation.

"I have learned that, when you are campaigning for as many months as Senator Clinton and I have been campaigning, sometimes you get careless in terms of the statements that you make, and I think that is what happened here," Obama said during a Puerto Rican radio appearance. "Senator Clinton says that she did not intend any offense by it, and I will take her at her word on that."