FDR won 4 terms despite saddling us with the biggest welfare state ponzi scheme we have today (not to mention providing the inspiration for even more welfare state ponzi schemes) and unnecessarily prolonging the Great Depression with additional big government schemes. Reagan won against Carter because he was a great politician and Carter was a lousy one. Obama is a great politician - his skill with a teleprompter is legendary, and he definitely interviews better than any of the candidates on offer from the GOP. Running against him isn't going to be any easier than running against FDR. It stinks that we don't have anyone with Reagan's combination of wit, charisma and gravitas.
On the other hand, there was no New Media back during the ‘30s and ‘40s. Also, I suspect that many people thought that what FDR did was necessary to help people and the country. From what I heard, ‘ol Hussein is getting rather low marks on the economy.