The nation's largest firefighters union and one of the Democrats' most reliable sources of campaign money says it will quit donating to federal candidates this year because members of Congress are not doing enough to support organized labor.

International Association of Firefighters President Harold Schaitberger says there is a more urgent need to spend money defending anti-union measures sweeping GOP-controlled statehouses across the country.

Schaitberger wants the move to send a message that lawmakers shouldn't take firefighters' support for granted. He says members of Congress should be doing more to speak out against efforts in states to take away collective bargaining rights and weaken union clout.

The union and its 300,000 members are among the most influential and biggest-spending lobbying groups on Capitol Hill.