WASHINGTON (Reuters) - Hillary and Bill Clinton are again teaming up on Barack Obama -- this time saying the first-term U.S. lawmaker, whom they have derided as inexperienced, would be a strong running mate on a Democratic presidential ticket headed by the former first lady.

In hailing Obama as a possible vice president, the Clintons are reaching out to him and, perhaps more importantly, to his backers, whose support she would need to defeat Republican presidential candidate John McCain in the November election.

“The Clintons are in a difficult position,” said Dennis Goldford, a political science professor at Drake University in Iowa, who has tracked the presidential race.

“If she wins the Democratic presidential nomination, she would need Obama’s supporters. But she needs to be careful. If this talk of him on the ticket is seen as a cynical maneuver, it could backfire and hurt her,” Goldford said.

Obama leads Clinton, a fellow Democratic senator, in a bruising race for their party’s presidential nomination, but neither is likely to reach the 2,025 delegates needed to become the nominee in the remaining state by state contests.

As Democratic leaders worry about the damage that could be done if neither has a clear lead by the August nominating convention, the party is also trying to decide what to do about election results from Michigan and Florida that do not count because of a dispute over when they were held.

The Clintons have charged that Obama, a charismatic lawmaker from Illinois, lacks the experience to handle an international crisis as president.

But since Clinton, a two-term senator from New York, won primary elections in Ohio and Texas, she and her husband, former President Bill Clinton, have touted Obama as a possible running mate.

‘ALMOST UNSTOPPABLE’

Sen. John Kerry, a Massachusetts Democrat who has endorsed Obama, derided that suggestion. “The first threshold question about a vice president is, are you prepared to be president?” Kerry told CBS’s “Face the Nation” on Sunday.

“So on the one end, they are saying he’s not prepared to be president. On the other hand, they’re saying maybe he ought to be vice president,” Kerry said.

Campaigning on Saturday, in Mississippi, the former president was quoted as saying his wife and Obama would be a dynamic duo, “an almost unstoppable force.”

The candidate said last week she and Obama may end up on the same ticket, with her on top.

US Democratic presidential candidate and Senator Barack Obama (D-IL) speaks in Laramie, Wyoming March 7, 2008. REUTERS/Rick Wilking

Pennsylvania Gov. Edward Rendell, a Democratic who has sought to rally support for Clinton in his state’s April 22 primary, backed the idea of Clinton and Obama teaming up. “It would be a great ticket,” Rendell told NBC’s “Meet the Press.”

Former Senate Democratic leader Tom Daschle of South Dakota, an Obama backer, mocked the idea.

“It may be the first time in history that the person who is running number two would offer the person running number one the number two position,” Daschle told “Meet the Press.”

Democratic Party Chairman Howard Dean said a battle over whether to seat Michigan and Florida delegates at summer convention could cost Democrats the presidency.

“The only thing that can beat us is that we’re divided,” Dean said on ABC’s “This Week.” He said a solution must be found that’s acceptable to both Democratic candidates.

Michigan and Florida defied the Democratic Party and held their presidential nominating contests earlier than permitted, costing them delegates at the party’s convention.

Officials in both states have discussed redoing their primaries. But the candidates, state parties and national party would have to agree on timing, funding and formats.