It wasn't a stretch for the Mad Men writers to put Don Draper and his advertising-agency colleagues to work in the 1960 presidential campaign for dour Richard Nixon, not dynamic John F. Kennedy. In those days, most professionals — like the hard-drinking, chain-smoking executives at the fictional Sterling Cooper — voted reliably Republican. But like the mores of Madison Avenue, the politics of professionals have changed. Today, college-educated professionals (especially women) are central to the modern Democratic electoral coalition.

One measure of that generation-long transformation is captured in these maps. They track how Barack Obama and John McCain performed in 2008 in counties with the most, and fewest, members of what Richard Florida, a senior editor at our sister publication The Atlantic and the director of the University of Toronto's Martin Prosperity Institute, has termed the "creative class." In his classic, The Rise of the Creative Class, Florida identified that group as people who are "paid to use their minds": artists, scientists, educators, lawyers, engineers, corporate executives, and even small-businesses owners.

Florida and his University of Toronto colleagues have used Bureau of Labor Statistics data to estimate the share of every county's workforce that fits in the creative class. National Journal then crossed their findings with the results of the past six presidential elections, dividing all counties into three tiers based on how much of their workforce belongs to the creative class.

As the maps show,  Obama in 2008 ran best by far in the counties whose share of creative-class workers ranks in the top third. In those counties, many of them hugging the coasts, Obama captured 57 percent of the two-party vote, compared with McCain's 43 percent. (The GOP nominee did best in some lightly populated Plains counties that score well on Florida's definition of the creative class but might not qualify in a classification limited to college-educated professionals.) Obama's share of the vote dropped to just 46 percent in the middle band of counties. And in the tier with the smallest shares of creative-class workers, McCain flipped Obama's margin (58 percent to 42 percent) from the top tier. McCain won more than four-fifths of these heartland-heavy counties.

As recently as 1988, George H.W. Bush won a majority of votes in the top tier of creative-class counties. But Democrats have captured a majority of the votes in those areas in each presidential election since, and Obama's 2008 showing was the strongest yet.

Given Obama's struggles among the white working class, holding these creative-class voters will be indispensable. In 2008, continuing a "class inversion" that has reshaped politics since the 1980s, Obama ran 7 points better among white voters with a college education than among those without. To win this year, Obama will probably need to widen that gap. (Two national surveys last week in fact showed it stretching to 8 percentage points.)

Still, Florida says, the allegiance of creative-class workers — often socially liberal, fiscally moderate, and skeptical of government solutions — remains unsettled. "The creative-class vote is still in flux," he says. "But as long as the Republicans are socially backward and the Democrats have a candidate like Obama or Hillary Clinton, [or someone who is] not an old-school Democrat, they will continue to pull ahead." 

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