Kevin Drum points out an interesting difference between Bush’s re-election campaign in 2004 and Clinton’s re-election bid in 1996:

[I]n 1996, of the people who thought the economy was in good shape, a total of about 63% voted for Clinton. In 2004, of the people who thought the economy was in good shape, an astonishing total of about 87% voted for Bush.

That’s a huge difference, and what it shows is that George Bush was much more successful at taking credit for the economy than Clinton was — and Clinton was no slouch in that department. As a result, although fewer people in 2004 thought the economy was doing well compared to 1996, Bush got far more total votes from that group than Clinton did.

There’s another way to interpret these figures, however. One key difference between the two races is that the state of the economy was a much more partisan issue in this campaign than 1996. Back then, Bob Dole was forced to run a character-focused campaign because he clearly couldn’t win on the economy, so Republicans and Democrats didn’t polarize as much in their opinions of how well it was doing. The 1996 exit poll shows that 55% of Americans thought the economy was good or excellent, including 42% of Dole voters and 70% of Clinton voters (a 28% gap). Only 10% of Dole voters thought the economy was in poor shape, compared with 4% of Clinton voters (a 6% difference).

In 2004, however, perceptions of the country’s economic well-being became a Rorschach blot, with both sides tossing out cherry-picked statistics to support the preconceptions of their supporters. According to the exit poll, 47% of Americans thought the economy was good or excellent, but that figure masks a huge divide between Bush and Kerry supporters. 13% of Kerry voters thought the economy was good or excellent, compared with 80% of Bush voters — an astonishing 67% gap that more than doubles the difference in 1996. 33% of Kerry voters thought the economy was in poor shape, compared with 2% of Bush voters — a 31% difference that is more than five times as great as the one in 1996. With that kind of polarization, it’s not surprising that the relationship between thinking the economy was good and supporting the incumbent was much tighter this time.

Update: Just to clarify, there are two different conceptual possibilities. One is that the economy drives vote choice (ie it’s an exogenous causal factor). The other is that vote choice drives perceptions of the economy (ie it’s endogenous). Obviously, both factors are important, but my suspicion is that the latter is more important in explaining the difference between 1996 and 2004. In short, people follow cues from elites, and this time the messages they received about the state of the economy differed wildly.