Residents in Wisconsin have voted in a recall election that could force the state's Republican governor out of office.

Exit polls indicate that the outcome could be very close. Governor Scott Walker is fighting to keep Milwaukee's Democrat Mayor Tom Barrett from taking his job. Walker defeated Barrett in the 2010 general election.

Shortly after taking office, Walker pushed through a law that sharply curtailed the right of most government employees to bargain for pay raises and other benefits, angering unions and Democratic activists. The law set off days of large angry protests at the state capitol in Madison. A grassroots campaign earlier this year gathered nearly 1 million signatures in a petition drive to force the recall election.

The recall effort in Wisconsin has attracted money and attention from Republican and Democratic supporters across the country. Walker raised $30 million to fight off the recall, far more than Barrett's $4 million. Democrats are hoping to offset the Republican money advantage with a major effort to encourage voter participation.

Walker, who has served 17 months out of a four-year term, said after casting his ballot on Tuesday that many residents are relieved the recall vote finally has taken place.

“I think most people are happy to have the election over. I think certainly for my family and I think most voters in the state wanted to have all of the attack ads off. They want to have their TVs back. They want to have their lives back. And I think that a lot of the folks out here from outside of the state will move on to Florida. They'll move on to Ohio and they move on to other states and we get back to business.''

Barrett commented that long lines at polling places are a sign of strong interest in the election.

“People are engaged in this. What we've noted in the last 96 hours is, around the state the energy has been building and building and building.”

The Wisconsin recall election is also seen as preview of the U.S. presidential race between incumbent Democrat Barack Obama and likely Republican Party nominee Mitt Romney. Mr. Obama easily won Wisconsin in the 2008 presidential campaign. But analysts say a Walker victory could mean that Romney will win the state in the November general election.

If he loses, Walker would become the third U.S. governor in history to be forced out of office in a recall election. The most recent successful recall vote was California Governor Gray Davis's loss to Hollywood action star Arnold Schwarzenegger in 2003.

Also facing a recall in Tuesday's election are Wisconsin Lieutenant Governor Rebecca Kleefisch and three Republican state senators.

Voters in California are also casting ballots on three controversial issues. Voters statewide are deciding whether to boost the tax on a pack of cigarettes by a dollar. The extra money wold be used for cancer research. Supporters say passage will encourage smokers to quit. Opponents call it another layer of bureaucracy.

Also, voters in the cash-strapped cities of San Diego and San Jose are voting on pension reforms for government workers.