For two primaries, several scenarios

The race at this point is at least as much about superdelegates as it is about voters in the remaining primary states, and a double Clinton victory could bolster her argument to superdelegates that Mr. Obama may struggle in November against Senator John McCain, the likely Republican nominee.

Whether that is enough to get them to make the leap of voting for Mrs. Clinton if Mr. Obama leads her after June 3 in the overall popular vote and pledged delegates is another question, which is why her campaign has renewed efforts to get Florida and Michigan delegates, elected in primaries carried out in defiance of the Democratic Party rules, seated at the convention.

One thing to keep in mind: the next contest is a week from Tuesday in West Virginia, another state where the demographics would seem to favor Mrs. Clinton.

2) Mr. Obama wins North Carolina and Indiana.

A double Obama victory would almost certainly mean lights out for the Clinton campaign.

“That would signal the end of the Clinton campaign,” said Jerry Meek, the chairman of the North Carolina Democratic Party, who has not endorsed anyone in the race. “I don’t see how she could continue.” He added, “She’d be fighting a losing battle.”

The ever-tenacious Mrs. Clinton has proven so eager to keep fighting that she might try to soldier on. It could be a tough, lonely road. Several of her advisers have said they would counsel her to quit the race if she lost both.

Even if she resisted, twin victories by Mr. Obama would go a long way to addressing concerns about the damage Mr. Wright inflicted on him, as well as his ability to “close the deal,” as Mrs. Clinton likes to say.

It is difficult to envision what her argument would be to stay in the race should that happen. More than that, Mr. Obama would no doubt encourage superdelegates, many of whom have been holding back to see how the voting plays out, to rally around him and bring the race to a close. And if there ever was a moment for the party’s big leaders to step forward, this would be it.

Matthew Dowd, the senior strategist for President Bush’s campaign in 2004, said, “It makes it almost impossible for her to win the Democratic nomination.”

3) A split decision.

The most likely split would be Mrs. Clinton winning Indiana and Mr. Obama winning North Carolina. That would almost surely mean the race would go on.

But it would not be easy for Mrs. Clinton to fight on if she cannot use Tuesday to make some progress in the battle for pledged delegates and the popular vote. Her own advisers say her best hope of getting superdelegates to vote against pledged delegates is if, after the final primaries on June 3, she is close to Mr. Obama in pledged delegates and ahead in the popular vote.

Mrs. Clinton now has 1,338 pledged delegates, according to a count and projection by The New York Times, compared with 1,493 for Mr. Obama. On Tuesday, another 187 delegates will be chosen, and after that, there are only 217 left. Under Democratic delegate allocation rules, Mrs. Clinton would have to win most of the remaining states by huge margins in order to chip into Mr. Obama’s delegate lead.

Mr. Obama’s total popular vote, including projections from the caucuses, is 14.8 million, compared with 14.2 million to Mrs. Clinton, not counting the votes in Florida or Michigan (his lead is slightly smaller if the caucus states are excluded).

It is not impossible for Mrs. Clinton to catch up, but it would require a series of lopsided victories — or a successful effort by the Clinton campaign to convince superdelegates and the party at large that the popular vote totals in Florida and Michigan should count in determining the will of the people, even though Mr. Obama’s name did not appear on the ballot in Michigan and neither candidate actively campaigned in either state. (If Florida and Michigan are counted, Mrs. Clinton has a slim lead in the popular vote by some calculations.)

“The math still favors Senator Obama, no matter what happens Tuesday,” Mr. Klain said.

But then he offered a caveat that could work in Mrs. Clinton’s favor. ‘This is the ultimate what-have-you-done-for-me-lately business,” he said, “and the more recent victories are going to count in people’s mind more than those older victories.”

This article, For Two Primaries, Several Scenarios, first appeared in Tuesday editions of The New York Times.

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