DELRAY BEACH, Fla. » The last time Bill Clinton and President Barack Obama spent so many hours on the campaign trail, dashing across the country to appear before adoring crowds, they were on different sides of the Democratic argument.

So that is exactly where Clinton began when he arrived here this week.

"It’s no secret that I tried hard to defeat President Obama in the primaries — and some of you helped," Clinton said, drawing a laugh from an audience in Palm Beach County, a place that was slow to embrace Obama two years ago.

"But I want to tell you something," Clinton continued, waiting for the crowd to listen. "It is my professional opinion that he has done a much better job than he has gotten credit for so far. And all elections are about the future, so what is the alternative?"

A coast-to-coast campaign swing by Obama this week, his biggest plunge into the midterm election season to date, drew considerable attention as he raised money for Democrats in five states over three days. But in a series of less noticed trips to every corner of the country, it is Clinton who has stepped into the role of defending all Democrats — Obama included.

Few people may have more credibility paying a compliment to Obama than Clinton. Tense exchanges between the two men were an unforgettable element of the 2008 presidential race, which by all accounts Clinton took far longer to get over than Hillary Rodham Clinton did.

"If you’re a Democrat, you need to hold your head up," Clinton said this week, delivering the pep talk of a coach who is disappointed with his team’s behavior. "I’m tired of reading about how we’re all belly-aching."

The former president has become one of the party’s best salesmen. He has long been in demand to raise money for Democratic candidates, but now there is a more pressing need: raising the spirits of Democratic voters, dispensing wisdom as he works to put the party’s political challenges into a broader context.

A decade after he was banished from the campaign trail — seen at the time as a liability to Vice President Al Gore’s presidential ambitions — Clinton is now the most sought-after Democrat, logging 29 stops so far this year with more to come in the fall. He has been embraced by Democrats wherever he goes, even as several candidates have run the other way when Obama has arrived in their state.

In Nevada, Clinton campaigned for Sen. Harry Reid in June. ("Why would you give away the Senate majority leader who has delivered time and time and time again?" Clinton asked a crowd in Las Vegas.)

In Pennsylvania, as he appeared this month for Rep. Joe Sestak in his Senate race, he warned about what could happen if Republicans win control of Congress. ("Give us two more years, and if we’re wrong, send us packing," he argued.)

And here in Florida, he made stops Monday in Palm Beach, Broward and Miami-Dade counties on behalf of Rep. Kendrick B. Meek, a longtime friend who faces an uphill Senate race. ("We haven’t built our way out of that hole as fast as anybody wanted, but it was a very deep hole," Clinton told his audience.)

Clinton, who gives precedence to Democrats who endorsed Hillary Clinton’s presidential bid, makes use of the perspective and latitude afforded to former presidents.

This week, as both Obama and Clinton passed through Florida, Democrats had the chance to see the distinct styles of the 42nd and 44th presidents side by side. Clinton is more cerebral, delivering a thorough recitation of the economic condition and discussing how the challenges of today are more severe than those of his time in office. Obama, after ticking through his policy achievements, edged closer to mockery of his rivals.

"Remember our campaign slogan, ‘Yes we can’?" Obama told a fundraising audience Wednesday evening at the Fontainebleau hotel in Miami Beach. "This year, their campaign slogan is, ‘No, we can’t.’ It’s pretty inspiring, huh? You know, you wake up in the morning and you hear ‘No!’ That just puts a little pep in your step."

By the time Obama returned to the White House a few hours later, he had raised millions of dollars for the Democratic Party in Florida, California, Washington state, Wisconsin, Ohio. Along the way, he honed his fall message and spent nearly as much time criticizing Republicans as promoting his own achievements.

For Clinton’s part, the utterances of a past president are not scrutinized as closely as the words of a sitting one, so he speaks a bit more bluntly now than when he was in office. His words are passionate, yet not personal. He conceded that the economic condition of the country has not improved as much as people hoped it would after Democrats took control of Congress in 2006 and the White House two years later.

"A year-and-a-half just wasn’t enough time to get us out of the hole we were in," Clinton said. "So I want you to stick with us. Give us two more years — two more years until another election. If we fail, you can throw us all out."

There is one word, though, that Clinton does not say: Bush.

Some Democrats have started mentioning former President George W. Bush with such frequency that you might think he had been written into the party’s platform. But Clinton spoke of the opposition in generic terms, focusing on Republicans in Congress. (Not only has Bill Clinton joined with Bush in raising money for rebuilding in Haiti, he also has become a close friend of Bush’s father.)

Jeb Bush, the former governor of Florida, said the Democratic Party was showing its desperation by spending so much time focusing on his brother.

"It’s a loser issue — they have a big L on their foreheads," Bush said in an interview. "If that’s all they’ve got, it’s a pretty good indication of the problems that the Democrats face in 2010."

And before Clinton took the stage here in Delray Beach — yes, he often still runs very late — a parade of local Democratic officials warmed up the crowd, with speakers offering sharp criticism of President Bush.

But when Clinton began speaking, he did not mention his successor in the White House at all, an omission that at least one woman in the crowd said she appreciated.

"I think that’s the politically correct thing to do. It’s also respectful," said Fay Gallam, a social worker from West Palm Beach, who waited hours to see Clinton for the first time.

As she walked away from the gymnasium, she beamed.

"He says just what we need to hear, and because he’s articulate, you can follow him and see the logic," Gallam said. "He’s more at liberty now, and President Obama is really under the gun."

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