Obama heads into Tuesday's primaries in Texas, Ohio, Rhode Island and Vermont riding a streak of 11 consecutive primary and caucus wins and leading the former first lady in popular vote, committed delegates, and fundraising.
In the conference call, senior Clinton strategist Howard Wolfson seized on those facts to reshape expectations about the Democratic contest.
"They are outspending us at least two to one in Ohio and Texas," Wolfson said. "If they are unable to win these states it sends a very clear signal that Democrats want this campaign to continue. Obama has every advantage going into this election. If Senator Obama is in fact the de facto nominee, he ought to win all four."
A loss for Obama in even one of the four states Tuesday would indicate Democrats have developed a case of "buyer's remorse," Wolfson said. "It would show that Senator Obama is having trouble closing the deal with Democrats."
As recently as Feb. 20, Clinton's husband, former President Bill Clinton, was singing a different tune about what it would take to keep her candidacy afloat beyond Tuesday.
"If she wins in Texas and Ohio, I think she'll be the nominee," the former president to a Beaumont, Texas, audience.
"If you don't deliver for her, I don't think she can be."
Bill Clinton's assertion that his wife must win both Texas and Ohio to keep her campaign alive reflects a widely held view among political analysts.
Polls now give her a modest lead in Ohio and show Texas is a toss-up, but earlier she had large leads in both states.
The New York senator campaigned with a backdrop of military leaders Friday in Texas, which has a large military presence.
She's spending all day Sunday rumbling across Ohio, and plans to stump there again Monday morning. Clinton will then return to Texas for a televised town hall meeting and she's purchased time to broadcast it across the state.
Her aides said no decision had been made on where to spend election night, but most betting was on Ohio, where the polls are more favorable.
Obama has announced he'll spend Tuesday night in Texas, one of the biggest prizes of the campaign. A win in Texas would allow him to counter the Clinton campaign's argument that although he's won more states, she's carried the big states like California, New York and New Jersey.
