With the Democratic presidential race potentially coming down to the will of the superdelegates - the nearly 800 party insiders and elected officials who can support the candidate of their choosing - the campaigns of and are pushing very different visions of how those still undecided should make their choice.
The Clinton campaign has suggested that superdelegates need to take a sober look at who they believe to be the best candidate - regardless of who ends up with an edge in delegates won during the primary and caucus season.
"The whole idea of superdelegates is they are supposed to exercise their independent judgment," Clinton said in New Orleans last month.
The senator insisted it would be a "disservice" to those who "have independent experience with candidates" not to allow them to use their experience as a basis for their judgment.
The Clinton campaign has set up a Web site, complete with embedded video clip of Democratic National Committee chair Howard Dean seemingly agreeing with Clinton, to further make the case.
The Obama campaign, meanwhile, has sent some mixed signals. But for the most part, they have suggested that superdelegates should follow the will of the people.
"We've got to make sure that whoever wins the most votes, the most states, the most delegates, that they are the nominee," Obama said last month. "I think it would be problematic if either Senator Clinton or myself came in with having won the most support from voters, and that was somehow overturned by party insiders. I think the people would feel as if the voters' voices had been discounted."
CBS News estimates that Obama leads Clinton among pledged delegates, 1,362 to 1,210. But among superdelegates, Clinton leads Obama 242 to 201. More than 300 superdelegates have yet to publicly state a position.
The superdelegate system was created in 1982, following a difficult decade for the Democratic party. Ten years earlier, Democrats had nominated George McGovern, who would lose badly to Richard Nixon in the general election. (Sensing that McGovern was too liberal to beat Nixon, many Democratic leaders tried, but failed, to keep him off the ticket.)
In 1976, the party nominated Jimmy Carter, who would go on to victory in the general election after a tough primary fight. But by the early 1980s, many Democratic leaders felt that Carter had been a poor president, according to Henry Brady, political science professor at the University of California at Berkeley. After having to back two straight nominees who many saw as disappointments, party leaders were looking for a way to have more control over the process.
"There was a feeling that they had gone to the extremes of a popular system and ended up with George McGovern and Jimmy Carter, and that was a mistake of the system," said Brady. "There was a feeling it had to be reigned in."
Superdelegates could also help head off ugly nominating battles by uniting the Democratic establishment around a candidate as early as possible. In 1984, when Walter Mondale wanted to make sure he had secured the nomination, he turned to the superdelegates to put him over the top before the party convention.
"The idea was to create a group of independent delegates who were free to coalesce around a nominee after a candidate emerged from the process with real strength," said Democratic strategist Tad Devine, who was Mondale's delegate counter in that race.
But the existence of superdelegates also created a potential perception problem. Democratic voters generally want the selection of their nominee to be as, well, democratic as possible - and the superdelegate system invited images of party bosses sitting in smoke-filled rooms, choosing their preferred nominee.
And even if the superdelegates were to try to follow the voters, it's not entirely clear what that means. Should they follow the will of their constituents, as Rep. John Lewis has suggested? (That might not be terribly democratic in the end, since superdelegates are not evenly spread throughout the country.)
Should they back the candidate with the most pledged delegates, even if the delegate counts don't reflect the popular vote? (It's possible that one candidate could end up with more votes and less delegates because of intricate party rules.)
And how will they factor in the results in Florida and Michigan, where delegates are not being counted because the states held their primaries early, in violation of party rules?
In a Feb. 25th CBS News poll, a majority of Democratic primary voters said that the superdelegates should back whichever candidate gets the most overall elected delegates. But party leaders seem inclined to maintain at least some control of the system, even if it means risking alienating the rank-and-file.
The best hope for Democrats to extricate themselves from the present situation is for one of the candidates to land a knockout punch that would make superdelegates coalescing around a nominee more palatable to voters, Devine said.
"If Obama had won in Texas and Ohio, this thing would have coalesced, and people would have accepted it," he said. Instead, the battle continues for a victory or series of wins that would provide an opportunity for that to take place.
"It has to do with momentum, it has to do with who's peaking," said Devine. "And that's the way it's supposed to be. If Obama looks like he has a glass jaw, he's not going to win."