Hillary Rodham Clinton retains her lead among suddenly critical Democratic Party insiders even as Barack Obama builds up his delegate margin with primary and caucus victories across the country, according to a survey by the Associated Press.
Of the 796 lawmakers, governors and party officials who are Democratic superdelegates, Clinton has 243 and Obama has 156. That edge is responsible for Clinton's overall advantage in the pursuit of delegates to secure the party's nomination for president.
According to AP's latest tally, Clinton has 1,135 total delegates and Obama has 1,106, with three of the delegates still to be awarded from Sunday's Democratic caucuses in Maine.
A candidate must get 2,025 delegates to capture the nomination.
The national party has named about 720 of the 796 superdelegates. The remainder will be chosen at state party conventions in the spring and summer. AP reporters have interviewed 95 percent of the named delegates, with the most recent round of interviews taking place last week, after Super Tuesday.
For the first time since AP began contacting superdelegates last fall, more than half of them - 399 - have endorsed a candidate. The remaining 320 or so delegates said they are either undecided or uncommitted.
With Clinton and Obama trading wins and losses as the primary and caucus season unfolds, the role of the superdelegates has been magnified and is causing anxiety inside and outside the campaigns.
If the current snapshot of the race holds, superdelegates could decide the nomination in favor of one candidate even if the other receives more votes in the party primaries and caucuses.
Obama weighed in Friday, saying that voters should determine whom superdelegates support, even as his campaign actively courts them.
"My strong belief is that if we end up with the most states and the most pledged delegates, and the most voters in the country, then it would be problematic for political insiders to overturn the judgment of the voters," he said. "I think that should be the guiding approach to determining who will be the nominee."
Clinton, speaking on Saturday, argued that superdelegates should make up their own minds and pointedly noted that Obama has the endorsements of superdelegates John Kerry and Edward Kennedy, both senators from Massachusetts, a state whose primary Clinton won.
"Superdelegates are by design supposed to exercise independent judgment," she said. "If Sen. Obama and his campaign continue to push this position, which is to the contrary of what the definition of superdelegates has historically been, I will look forward to receiving the support of Sen. Kerry and Sen. Kennedy."
Unlike pledged candidates secured through a primary or a caucus, superdelegates can vote for whomever they choose, and they are not required to vote for the candidate they endorse.
Indeed, some superdelegates who had endorsed other Democratic candidates have already switched to Clinton or Obama or are reconsidering their earlier choices.
The Democratic Party introduced superdelegates to the nominating process after the 1980 election. Superdelegates make up about 19 percent of the overall delegates.