The political equivalent of buyer's remorse is voter's remorse. Often it leads voters to revise their assessment of a former president. A once-unpopular chief executive begins to look better, many times in contrast to voters' view of the current occupant of the White House. So, buyer's remorse could affect the 2008 election.

Does former President Clinton help or hurt his wife's campaign for the White House? A Gallup poll taken for USA Today found that 70 percent of Americans think that Bill Clinton will do Hillary Rodham Clinton's campaign more good than harm. Only 25 percent think that he'll do more harm than good.

An element of nostalgia for Bill Clinton's presidency has set in. "Hey, you can run again!" a man shouted at the former president when he was inducted into the Voting Rights Hall of Fame in Selma, Ala., last month. "Now wait a minute," Clinton responded. "Well, I can't. You need to think about something else."

Shortly after Clinton left office in 2001—in the wake of the controversy over his presidential pardons—only 42 percent of Americans held a favorable opinion of him, Gallup found. That number has climbed to 60 percent. Clinton's popularity has gone up as President Bush's has gone down. Bush's job-approval rating stands at 34 percent in the Gallup/USA Today poll. More than twice as many Americans (71 percent) describe Clinton as a good president.

The more people turn against Bush, the better they like his predecessor. Times were good. Americans felt secure in the world. So what if he got impeached. "I believe Bill Clinton was a good president," his wife said at a Nevada voter forum. "I'm very proud of the record of his two terms."

The same kind of voter's remorse about President George H.W. Bush benefited his son in 2000. Just 34 percent of voters held a favorable opinion of Bush I shortly before they fired him in 1992. By 2000, that number had climbed to 73 percent. So what if the economy was a disaster when he left office. The first President Bush was remembered as a man of good character. His son drew upon that image when he said at the 2000 Republican National Convention, "I want to thank my dad, the most decent man I have ever known."

George W. Bush went on to pledge fidelity to the Bush brand by promising, "When I put my hand on the Bible, I will swear to not only uphold the laws of our land. I will swear to uphold the honor and dignity of the office to which I have been elected."

Bush has been without majority approval for more than two years. That is the longest span of unpopularity for any president since Harry Truman.

While in office, Truman was massively unpopular. In campaigning for Dwight Eisenhower to succeed him, Republicans tagged Truman a failure in dealing with "Korea, communism, corruption." Soon after Truman left office, however, voter's remorse set in. He is remembered today as one of the nation's outstanding presidents.

Voter's remorse has helped Bill Clinton to play a central role in his wife's fundraising. The former president attended or hosted 16 events in the six weeks before the March 31 fundraising deadline for the first quarter of the year. "It's a lot more than anyone expected two months ago," a Hillary Clinton fundraiser told The New York Times. "President Clinton is a competitive guy, and he has said himself that the March 31 fundraising deadline was 'the first primary.' "

Hillary Clinton's totals were impressive: $26 million raised over a 10-week period, according to her campaign, in addition to the leftover $10 million that she transferred from her 2006 Senate campaign fund. Her numbers outpace the $8.9 million raised in the first quarter of 1999 by Al Gore and the $7.6 million raised then by George W. Bush. Her numbers also dwarf the $7.5 million that John Kerry and John Edwards each reported for the first quarter of 2003.

There is some risk, of course, in having the former president play a conspicuous role in his wife's campaign. In the Gallup/USA Today poll, 76 percent of Americans said that the state of Hillary Clinton's marriage should not matter when people consider whether to vote for her for president. At the same time, 58 percent said they believe that it will matter.