Jim Geraghty writes the Campaign Spot on NRO.

Republicans relish the tempting thought of history repeating itself: an incumbent Democratic president, widely perceived as a disappointment or a failure, heads into an election with seven out of every ten Americans believing the "country is in deep and serious trouble." After dismissing his Republican challenger as an unserious joke, the hubristic incumbent loses the popular vote by a wide margin and the Electoral College by a landslide.

And just think, Republicans have been comparing Barack Obama to Jimmy Carter since 2008.

While Mitt Romney’s presidential campaign is sure to enjoy the comparisons of this year’s presidential election with the one 32 years ago, Republicans shouldn’t fool themselves about the difficulty of the task before them. While it’s possible that Romney could win big, any serious examination of this race should recognize several enormous changes that have taken place in our national political environment in the past three decades, shifts that work against a repeat of Reagan’s rout of Carter....