From CBS News correspondent Jeff Glor and producer Phil Hirschkorn.
Despite all the primaries and caucuses and millions of people voting, it is growing increasingly possible that neither Barack Obama nor Hillary Clinton will secure a majority of delegates needed to win the Democratic Party's presidential nomination when the contests are over in June.
"Neither will have enough," Clinton campaign adviser Harold Ickes told reporters in a conference call Saturday.
If his forecast is correct, that means a group of 796 so-called "superdelegates," or one out of every five of the 4,049 delegates going to the national convention in Denver this August, may hold the power to pick the party's nominee.
"Both of the candidates are going to need them to nail down the nomination," said Ickes.
The current delegate count, according to CBS News, allocates 1,284 to Obama, including 1,124 elected and 160 superdelegates. Clinton has 224 superdelegates and 984 elected ones for a total of 1,208.
About half of the superdelegates hold elective office, like U.S. Senator Bob Casey of Pennsylvania.
"It would not be good for the Democratic Party if this went to the convention, because I think we need to unify a lot sooner than that," Casey tells CBS News.
At least through his state's primary in late April, Casey plans to remain uncommitted, despite pleas by the Obama and Clinton campaigns for him to make a choice.
"We've had contact with both sides asking for help and sometimes advice," Casey says. He considers candidates electable in November, but prefers for the primaries to play out and possibly tip the nomination contest one candidate's way.
"I think there will be a convergence, or a confluence really, of momentum and consensus," the senator says.
Casey and dozens of superdelegates who hold office have received more than $904,000 in campaign contributions over the last three years - $698,000 from Obama's political action committee and $206,000 from Clinton's, according to the Center For Responsive Politics. The center reported this week that 43 percent of Obama's pledged superdelegates and 12 pecent of Clinton's were recipients.
The other half of the superdelegates are Democratic National Committee officials like Ralph Dawson, a New York lawyer appointed by party chairman Howard Dean, a college friend. Because Dawson is still uncommitted, he gets phone calls and emails all the time.
"From DNC members supporting one or another candidate. Within my family, differences of opinion," Dawson tells CBS News.
Support Hillary, some tell him, "She would be the first woman candidate. Are you sexist?" they ask.
Support Obama, press others, "This might be the only time that an African-American is in this position for the next 30 years. What are you gonna do?"
Dawson takes it all in stride. "I don't feel pressured because people are calling me. I think you always want to do what's right for the country and the party," he says.
The Democrats created superdelegates after the 1980 campaign to help ensure their nominee was mainstream and electable. South Carolina congressman Jim Clyburn, the number three Democrat in the House of Representatives leadership, describes the group as a "safety valve" in case the frontrunner falters.
"They have never before provided the sole margin of victory in a nominating process; this time they will," says Democratic strategist Tad Devine, who tracked superdelegates for winning nominees Jimmy Carter in 1980, Walter Mondale in 1984 and Michael Dukakis in 1988. Devine is cautioning superdelegates to be patient.
"I think the risk of superdelegates moving now is that there will be a perception amongst the voting public that this process has been decided in back rooms and not in voting booths," he says.
Still, the trickle of superdelegates announcing their prefererence continues. On Thursday, Wisconsin superdelegate Stan Gruszynski, who spent ten years in the state legislature, came out for Obama. "I don't really see any reason why I should sit back and be silent, when my vocalizing my judgment can make a difference," Gruszynski tells CBS News. "It may help people who know me to decide."
Currently behind in delegates won in voting booths, Clinton is counting on her current edge with superdelegates like Texas Democratic party activist David Holmes, to overcome Obama's overall lead.
"I really feel Hillary Clinton has the experience and the determination to move our country forward and repair our reputation in the world," Holmes tells CBS News. "I am gonna stick by my commitment. It would have be something quite significant to change my mind."
Since her campaign believes neither Senator will win enough elected delegates in the primaries and caucuses to secure the nomination - the magic number of 2,025 - a superdelegate like New Jersey school secretary Roz Samuels is perhaps Clinton's worst nightmare. Samuels tells CBS News she had wanted to see a woman in the White House but switched her allegiance this week to Obama.
"I like his energy. I like the way he has brought the young people into the forefront. And I like his views on Iraq," Samuels says. "No one pressured me."
Longtime Georgia Congressman John Lewis - a civil rights movement leader who backed Clinton - is one of the first superdelegates in office to reveal he may switch to Obama too, if it's left up to the superdelegates at the convention.
Ultimately, Obama's campaign may have an ally in California Democrat Nancy Pelosi, the Speaker of the House of Representatives, who says her party will be in trouble if the superdelegates, in the end, do not reflect the will of the voters. Clinton's campaign, not surprisingly, says superdelegates should be able to vote independently for whoever they want.