By now, it's a virtual certainty that nearly 800 people chosen neither through primaries nor caucuses will ultimately pick the Democratic Party's presidential nominee. Most of these so-called "superdelegates" are party officials, state governors and members of the House of Representatives.
But one superdelegate group is especially close to candidates Hillary Clinton and Barack Obama — their fellow Democratic senators. And many of them have yet to make an endorsement.
There are 49 superdelegate senators. Thirteen have endorsed Clinton, and 17 have come out for Obama. That leaves 19 Senate Democrats still uncommitted. Missouri's Claire McCaskill was an early Obama supporter, and she's doing her utmost to win over those undeclared colleagues:
"I say, you know, come on in, the water's fine. It's a tough decision, and you're going to disappoint some people, but if you're a superdelegate, it should be because you're used to making tough decisions. It kind of goes with the territory," McCaskill says. "So it's time to buck up, make the decision, announce it, and let's get a nominee."
Senators who have decided to take the plunge during the past month have all jumped into Obama's delegate pool. Pennsylvania's Bob Casey says he did so two weeks ago, once he realized that he wants Obama as the next president.
"Once you're decided, and you're a public official, what do you do? Do you sit on the sidelines, or do you get involved? I chose to get involved, and hope we can help," Casey says.
Like Casey, Virginia's Jim Webb is a freshman senator. Webb says it's fine if his colleagues want to endorse Obama or Clinton:
"As for me, I'm staying out of it. If I had really strong feelings about one candidate or the other, I would be endorsing them, but I think they both can do the job," Webb says.
Voters in Virginia's primary chose Obama over Clinton by nearly a 2-to-1 margin. Still, Webb says that outcome won't determine whom he ends up backing:
"I think Barack did very well in the state, and I respect him for it," he says. "When people are asking me for my personal endorsement, I have to be able to say one way or the other that I believe one of those two candidates markedly would be better as president. That's the criterion that I'm using, and I think they both would do a good job, so that's where I am."
And that's where Connecticut's Chris Dodd expects a good number of his undeclared Senate colleagues to remain, just as long as they can. Dodd strongly endorsed Obama after dropping his own bid for the White House, but he understands why some senators would want to hold back.
"You've got divided constituencies in their states, and they're going to hope this resolves itself with them not having to get in the middle of it. And if it can, then they haven't necessarily hurt themselves with their own base. And I understand that politically, particularly with newer members, first-term members," Dodd says.
But more senior senators have also kept their lips sealed and their options open. Herb Kohl is in his fourth term as the senior senator from Wisconsin, where Obama beat Clinton in the primary by 17 percentage points:
"There may or may not come a time when what I think is important," he says. "You know, we'll see how events unfold."
Other Senate superdelegates say they fear that making an endorsement now might undermine support for bills they have pending in the Senate. That's the reason Oregon's Ron Wyden gives for not saying whom he backs.
"I'm going to be neutral in this race, because now that we've got the first bipartisan universal coverage health bill in the history of the Senate, I don't want people to spend their time saying that this is Obama care or Clinton care — I want them to focus on the fact it's bipartisan," Wyden says.
He says he'll only announce whom he prefers once the primaries are over, including Oregon's late next month. And there are other senators who have made an endorsement but who could still switch. Washington state's Maria Cantwell, who came out early for Clinton, says the vote she casts at the Democratic convention in August could ultimately be determined by several factors that right now all favor Obama.
"The most pledged delegates, the most states won, and the number of states won ... all of those factors would then lead somebody to start down a path of saying, 'OK, how are we going to get our nominee?'" Cantwell says.
But another Clinton backer, Indiana's Evan Bayh, says if it's the popular will that superdelegate senators want to reflect, they should not be looking at who wins the most pledged delegates:
"The pledged delegates are simply an intermediary for the will of the people themselves," Bayh says. "So in a race this close, why not go to the real thing, and see who won the aggregate popular vote? It seems to me that's a better indicator of the will of the people than these delegates that, as you know, are awarded in all sorts of Byzantine ways from state to state."
Whatever they base their decision on, the colleagues of Obama and Clinton will ultimately have to choose one or the other. At least for now, in the Senate's superdelegate derby, Obama seems to have the inside track.