He will be running for in Pennsylvania as a Democrat in 2010 in what could be a fraught and dramatic campaign, and if he's primaried, he may need buckets full of money to prevail. This is one...creative...method of raising that money.
The idea is pretty simple. Specter is an advocate in the Senate for setting a $40 billion annual funding baseline for the National Institutes of Health--and if he's defeated at the polls, that bill will lose one of its most storied and influential sponsors. But if he wins, then the money raised by Specter for the Cure will, de facto, also support Specter's various other, eclectic legislative priorities.
But that's not how he sells it. According to the website, "Arlen Specter will seek re-election to the United States Senate. Without Arlen Specter back in the Senate to see it through, Specter for the Cure could be lost to the ordinary politics of Washington that kills real change." Some of the money he uses in that re-election bid will surely come from people who think they're giving to a cancer charity.
Maybe if he loses he'll give an amount equal to what he raises via specterforthecure.com to a reputable cancer charity. More likely, though, the money will just be lost.