Following the 1976 GOP convention, it was pretty clear that Reagan would be the party's nominee in 1980. Coupled with the fact that the incumbent was a notoriously weak politician, having barely beat the Republican the previous election following several years' worth of controversy, and the country's economy/foreign policy was in shambles--it's easy to see why Reagan curb-stomped Carter in 1980. He ran a good campaign, but no huge surprises here.
Clinton ran an excellent campaign in 1992, and successfully built momentum as the primary went along, and had to do so partially because the winners of Iowa and New Hampshire were certainties going into the primary. It's hard to give him an enormous amount of credit for the general election victory, considering there were so many external factors affecting the outcome (economy, third party candidacy, running against a fourth term of Republican Presidents, etc.).
Considering the state of the country at the time, Obama's general election performance wasn't too impressive. However, he ran an incredibly skilled campaign against a skilled politician who had the party's full support, and most people--going into the 2008 election--simply assumed would be the party's nominee.
Have to go with Obama's 2008 campaign, specifically the primary. He achieved a seemingly impossible task.
The economy in 2008 was far worse then it was in 1992. In 1992 the economy was in recovery stage while 2008 was the peak of its recession
The unemployment rate was lower in 2008 than in 1992. Just sayin'....
But I understand your point. We were in a full-blown recession in 2008 as opposed to a weak recovery from a recession in 1992. Still, I'm not sure which one is actually more hurtful to the incumbent party. It seems like most voters don't start feeling the pain of a recession until right after it's over. That's partially why Dems got clobbered in 2010...while the economy may have technically been in recovery, the unemployment rate was way higher than it had been for most of the recession.