You’d never know it by the way the union bosses spend members’ dues.

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%.

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. […]

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.