Yes, it does. But the factors that predict our wages predict our vote even better.
This is the general theory of wages and voting preferences in a sentence: The more income you make, the more likely you are to vote Republican ... or to vote, at all.
It's a long-held political axiom, and it's upheld in a recent study by PayScale, the nation's largest private salary survey company. In research shared with The Atlantic, they showed that Americans who make less than $70,000 (about 70% of the country) are considerably more likely to vote Democratic. Those making more than $70,000 are more likely to vote Republican.
But the relationship between wages and voting isn't as simple as two lines making an X. Let's break it down by gender, geography, and demographics.
The gender gap shows up in PayScale's survey, as well. At the $50,000 point and above, men prefer Romney. But women making between $50,000 and $200,000 are still more likely to break for the president. It is only in the top 1% of female earners that PayScale found a clear Republican preference.
A reasonable objection to the General Theory of Wages and Voting is this: If rich people are more likely to vote Republican, how come so many rich states -- California and the northeast, for example -- always vote Democrat, while some of the poorest states vote Republican?
Once answer is that income matters more for voter preferences in Red America than in Blue America. "In poor states, rich people are much more likely than poor people to vote
for the Republican presidential candidate," political scientist Andrew Gelman found, "but in rich states (such as Connecticut),
income has a very low correlation with vote preference."
The four (small) graphs to the right from Bob Shapiro measure likelihood to vote Republican against income. As you can (hopefully!) see, the line is steepest in Mississippi (top left), flattest in Connecticut, and flattening in Virginia and Ohio. In other words, incomes are a much better predictor of voting preferences in deeply red states. In swing states, they are a moderately accurate predictor, and in rich states like Connecticut, practically everybody is equally (un)likely to vote Republican.
But there's something else at play here...
It's possible that how much money we make isn't a "swing variable," but instead, the variables that determine how much money we make are the most important
influences for our vote.
Take race, age, and education, for example. In one astonishing poll this summer, Romney attracted zero percent of the black vote, and president still leads 72%-22% among Hispanics. Those are considerably larger advantages than either candidate has at any particular income level.
So one thing we might be seeing in the Mississippi graph above is that poor blacks in the south are more likely to support Democrats and richer whites are more likely to support Republicans. Perhaps the more determinant factor isn't income but race. Indeed, Obama is struggling to win more than 40% of the white vote, while George W. Bush won a similar share of the lowest-income Americans' vote in 2004.
People who go to college are more likely to make more money, so you'd think they're more likely to vote Republican. In fact, college-educated voters have become considerably more Democratic since the 1980s at every age level. You might think it's just women. It's not. White college-education men have become *much* more Democratic since the 1980s while white voters without college degree have become significantly less Democratic. About 43% of white college-educated men voted for Obama in 2008 after breaking 2-1 for Republicans in the 1980s. Meanwhile, according to Larry Bartels at Princeton University, white voters without college degrees have become significantly less Democratic recently; although the trend is confined mostly to the south.
The upshot is that just because there is a strong relationship between income and voting preferences doesn't mean that it's income itself -- or, certainly, income alone -- that shifts our preference. Geography, education, race, and marital status all influence both our earning potential and our vote.