People who describe themselves as socially liberal have been outnumbered by moderates and social conservatives since at least 1999. Not anymore, according to a new Gallup poll:

Social conservatives and social liberals have pulled even at 31 percent apiece, with moderates making up the remaining 34 percent of the population.

This is mostly due to a change of heart — or at least a change of identification — among Democrats, who are much more likely to describe themselves as liberal than they used to be. It probably also reflects significant, fast-moving shifts of public opinion on social issues like same-sex marriage and marijuana legalization.

Republican opinion, on the other hand, has barely shifted: 53 percent describe themselves as conservative, down from 57 percent in 2001. And although liberals have gained ground on economic issues, too, the shift isn't nearly as dramatic. Self-described conservatives on economic issues still outnumber liberals two to one.

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