You often hear that politicians can't think long-term. But in the last few months, Congress has shot down various short-term stimulus measures because they add to our long-term debt. Maybe they're just reading the polls: Americans now consider debt as threatening to the United States' well-being as terrorism. Perhaps it makes sense to fear red ink as November crucial issue?

Or perhaps not. History suggests that income growth in an election year determines outcomes far more than debt accumulation, or even the unemployment rate. Ezra Klein paints the picture with charts (click on them to see larger pictures):

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There are a couple directions to go with the results. The first, simplest explanation is Ezra's: it's (always) the economy, stupid. Candidates matter, but circumstances matter more. Incumbents' chances grow with peoples' wages. Under this interpretation, Democrats are probably doomed no matter what.

Debt accumulation matters, but it's almost never in the ruling party's interest to actually call for debt reduction -- in the form of tax increases, spending cuts, or entitlement overhauls. After all, reducing your debt often means breaking promises, and nobody likes politicians who reveal themselves as liars:

-- In late 1978 Jimmy Carter made a tough speech about slashing the deficit to fight inflation. He lost 15 representatives and three senators in next month's election.

-- In 1984 Walter Mondale proposed deficit-reduction as the defining issue of the election. He lost 49 states.

-- In 1988 Michael Dukakis lost to the first Bush pledge for "no new taxes." In 1990 George H. W. Bush raised taxes to reduce the deficit. He lost in 1992.

-- In 1993 President Clinton passed a deficit reduction plan over universal Republican opposition. He lost the midterms brutally in 1994.

This does not prove direct causality, but it sends electeds a clear message. Americans say they hate the disease of deficits. But they often punish politicians for offering the cure.

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