From Eleanor Clifts article in Newsweek:
The reason he's working so hard on his wife's behalf is that he sincerely believes she would make a good president, better than he was, if daughter Chelsea's word is taken to heart. He's also doing penance for how much he humiliated her when he was president, and even for some of his missteps in this campaign, mostly having to do with race. But perhaps most important, Clinton understands that if Barack Obama is elected, his presidency becomes an asterisk.
It's less about the historic nature of the first black president, a title once bestowed on Clinton by writer Toni Morrison, than it is the levers of power Obama would have at his command. If Obama wins in November he'll have a majority in the Senate close to 60, and at least 15 more seats in the House, numbers that signal a true governing mandate from the people. Clinton was forced to play defense, too often settling for mainly symbolic gestures like advocating school uniforms when only two years into his term the Republicans won control of both houses of Congress for the first time in 40 years. Clinton knows that through the long view of history, he'll be viewed a lot less positively if the bridge he set about building to the next century leads to a president with the ability to overshadow him legislatively, as opposed to one who carries on his name and legacy.
There is no shame in coming in second, should that be her fate. The steps she's taken to rejuvenate her campaign, bringing in more voices and half-firing Mark Penn, the architect of the "Ready on Day One" theme that never captured the voters' imagination, have probably come too late to close the gap without tearing the party apart.
What will play better against McCain than the "experience" card? A fresh start—and that's a hard truth for Hillary to hear, and even harder for Bill.
http://www.newsweek.com/id/131524