PRINCETON, NJ -- A majority of union members say they would vote for Barack Obama in the 2012 presidential race, although their support is by no means monolithic. While 57% of union workers who are registered to vote would support Obama, 35% would vote for Mitt Romney. Workers who are not union members tilt toward Romney over Obama, 48% to 44%.

Roughly 12% of workers interviewed April 11-June 5 in Gallup's Daily tracking who are registered voters say they are union members.

The tilt toward support for Obama among union members is not surprising. Not only have unions been strong and vocal supporters of Democratic presidential candidates historically, but previous Gallup analyses have shown that union members are significantly more likely than nonunion members to be Democrats; this is particularly true for state government employees.

The relationship between unions and politics was starkly evident this past week in Wisconsin, where unions fought hard but unsuccessfully to recall the incumbent Republican governor, Scott Walker, who had pushed for restrictions on state government employee unions.

Union members who work for the government are little different from private-sector union members in their preferences for Obama over Romney. Nonunion workers in the private sector, however, tilt their support to Romney. Government workers who are not members of unions still support Obama, but by a slim margin over Romney.

State government union workers are slightly more likely than the average government union worker to support Obama. Still, about three in 10 state workers who are union members and are registered to vote support Romney, underscoring the finding that union members are modestly diverse in their presidential preferences. There were too few union members working for the federal government in this April 11-June 5 sample to analyze meaningfully.

Implications

Union voters are substantially more likely to vote for Obama than for Romney, at a time when the overall race is essentially tied between the two major-party candidates. Still, a little more than a third of union workers support the Republican Romney -- despite evidence of strong union support for Democratic candidates, including Milwaukee Democratic Mayor Tom Barrett, who lost his bid to oust Gov. Walker in Wisconsin last week.

Much of the focus on union members over the last year has been on government workers, but these union members are statistically no more likely to support Obama than are union members who work in the private sector. Even state government workers, who tend to be more Democratic than other government workers, are just a few points higher than the overall union average in their support for Obama.

All in all, union workers provide a substantial bloc of support for Obama's re-election efforts, although their impact on the presidential race will be limited by their size -- just about 12% of employed voters are union members -- and the fact that a sizable minority support Romney. Still, in crucial battleground states this fall, the vote and efforts of even small groups may end up making a difference.

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