In 1980, the reason why Reagan won as convincingly as he did was because Carter had so screwed things up, people had no choice to vote for Reagan. And the Iranian hostage crisis was just a final nail in the coffin. What the GOP needs to do this time around is play up Obama's failed promises:
Afghanistan-Still going on
Iraq-We're still there
Healthcare-Turning into a nightmare for Obama
Cap & Trade-dead in the water
Economy-Been as stagnate as a mud puddle and jobs aren't getting any better.