This report is from the Scotsman, the same paper that published Samatha Power's "monster" comments.
It is a credible paper, but as a foreign source, it probably deserves an extra level of scrutiny.
Note that all sources in the article are anonymous.
EDIT: It's also not clear that the Scotsman's sources believe this would happen before Pennsylvania. In fact, the implication more seems to be that this is how the endgame might play out after Pennsylvania.
DEMOCRAT grandees Jimmy Carter and Al Gore are being lined-up to deliver the coup de grâce to Hillary Clinton and end her campaign to become president.
Falling poll numbers and a string of high-profile blunders have convinced party elders that she must now bow out of the primary race.
Former president Carter and former vice-president Gore have already held high-level discussions about delivering the message that she must stand down for the good of the Democrats.
"They're in discussions," a source close to Carter told Scotland on Sunday. "Carter has been talking to Gore. They will act, possibly together, or in sequence."
An appeal by both men for Democrats to unite behind Clinton's rival, Barack Obama, would have a powerful effect, and insiders say it is a question of when, rather than if, they act.
But the party's top brass have concluded her further participation in the race can only harm the party as Republican nominee John McCain strives to take advantage of her increasingly bitter battle with Obama.
Both Carter and Gore occupy the rarefied position of elder statesmen – in addition to their White House past, both are winners of the Nobel Peace Prize, giving them additional gravitas to carry the party with them.
Neither of them is likely to object to the role of bringing down the curtain on Clinton. While neither man has formally endorsed either her or Obama, both have clashed in the past with the Clintons.
A number of options are being considered by the higher echelons of the Democrats, but they fall roughly into two categories. One is for Carter and Gore to go to Clinton privately and ask her to step down. The other is for both men to appear in public and endorse Obama – a move which would see a majority of superdelegates go with them.
The campaign to force Clinton to make an early exit is being masterminded in Congress, home to the most influential of the superdelegates. Senate Leader Harry Reid and House Speaker Nancy Pelosi have called on superdelegates to hold an unofficial congress in early June to anoint a winner, rather than waiting for the convention in Denver.
Yet some in the Democratic elite are wary of moving too soon. Polls show that 30% of Clinton's supporters would vote for McCain if she fails to become the nominee. To close off Clinton's bid before millions have had the chance to vote risks causing the very split that officials are desperate to avoid.
But a loss to Obama, or even a single-digit victory, in Pennsylvania will seal Clinton's fate. Pennsylvania is the last big state left in the race, and the last chance for Clinton to claw back Obama's delegate lead. "If he (Obama] wins (Pennsylvania] flat out, I think the big foot will come down," a source said.
Anything less than a resounding victory by her will probably see the race choked off ahead of the final primaries on June 3.