The one promise that President George W. Bush made during his re-election campaign that made me enthusiastic about voting for him was that he said he would reform Social Security so that people could direct some of their money into private accounts. To this day, I don't know why so many people oppose this—no one has to redirect their Social Security funds, but it's an option.
In the days just after his re-election, he tried to make good on his promise, but the Democrats demagogued the issue, as they tend to do (even Biden did so in the VP debate this year), the public soured, Republicans didn't push, and the whole endeavor died.
The weird thing is, back then, I don't remember anyone saying, "George W. Bush campaigned on this, and he won, therefore we should do it," which seems to be the argument for raising taxes today. In another example of inconsistency (note: I'm not calling this hypocrisy), in 2005, with a Republican President that the left despised, mandates and campaign promises meant nothing. In 2012 with a Democrat President that the left adores, the exact reverse.