Why the Obama coalition might still flop.

BARACK OBAMA’S REELECTION is evidence of a Democratic realignment that dates back almost two decades. This might seem like a bold claim. After all, President Obama won by 3 percentage points—certainly no landslide. And many Republicans insist that his victory was a passing phenomenon. “There is no realignment, just a loss after a rain delay killed our starter’s momentum,” the radio talk-show host Hugh Hewitt wrote. Political scientists, too, were skeptical about the election’s significance. George Washington University’s John Sides insisted that a realignment cannot occur without “an extended period of party control,” and “a notable shift in policy.” Even those who discussed the election as marking a major change in U.S. politics generally confined themselves to one idea: namely, a growing Hispanic population finally displayed its power at the polls.

But the Republicans are in denial, and the political scientists are clinging to an outdated model. Due to the decline in party organization and the rise of independent voters, realignments have become more gradual and less comprehensive. They go by fits and starts. The conservative Republican realignment began in 1968, was waylaid by Watergate, and only resumed in 1980. At its height, during Ronald Reagan’s presidency, Republicans did not even control the House. The current Democratic realignment began in the Bill Clinton years, hit speed bumps during the 2002 and 2004 elections (thanks largely to September 11), and hit another bump in 2010, when voters blamed Obama for the flagging recovery. It resumed in earnest this year and is going strong.

By the same token, realignments don’t necessarily result in dramatic policy shifts. California went deeply blue in the mid-’90s but has been paralyzed on the policy front for years. Nationally, both Bill Clinton and Obama have had trouble getting things done even as public opinion was shifting their way. The reason for this is that U.S. politics consists of not one but two systems—a visible electoral process that supplies officeholders and a less visible machinery of interest groups and lobbies that influences both elections and governing.

In the wake of Obama’s reelection, the crucial question is whether the political realignment taking place will lead to an equally dramatic breakthrough for his agenda, which includes increasing spending on education and infrastructure and counteracting global warming. At the polling booth, Democrats have gained the upper hand. But outside the electoral arena, powerful forces will continue to encourage Republican intransigence. Only by taming and defeating them can Obama and his party deliver on the promise of realignment.

THE CURRENT Democratic dominance is the result of the shift of voting blocs away from the Republican Party and the growth of existing voting blocs within the Democratic Party. Women, young voters, and professionals were once predominately Republicans but have increasingly become Democrats. Professionals—who can be very roughly identified in exit polls as voters with advanced degrees—now make up approximately one-fifth of the electorate. They favored Obama by 55 to 42 percent. The margins are even higher in high-tech states like New Jersey, where they went for the president by two to one.