MADISON, Wis. — A long anticipated recall drive aimed at removing controversial Gov. Scott Walker got under way today with opponents of the freshman Republican fanning out across the state to gather the first of the 540,000 signatures they will need to force a vote.

"I have never seen any individual of either political party do so much damage to things I care about," said Severa Austin, a professor at the University of Wisconsin-Madison, as she gathered signatures in front of the statehouse which Republicans control.

Walker, swept into office in the Republican electoral tide last November, infuriated Democrats and unions from the first with measures that curbed collective bargaining rights and benefits for public workers and cut school spending.

The actions triggered months of dramatic political upheaval, but Wisconsin law delayed the start of any recall effort until now. Opponents of Walker found encouragement recently from Ohio,  where voters in a statewide referendum overturned a similar anti-union measure put in place by that state's new GOP governor.

Even before the first petitions were signed, Walker launched a vigorous defense of his leadership in a TV spot that aired during the closely followed Monday night football game between the Green Bay Packers and the Minnesota Vikings.

Stephan Thompson, executive director of the state GOP, also released a statement praising Walker for keeping a lid on taxes while balancing the budget and cutting costs for schools and local governments.

Recall supporters have 60 days to gather enough valid signatures to force a vote, which would likely take place sometime in the spring. No Democrats have yet stepped forward to run against Walker if the recall qualifies for the ballot, though some prominent political names in Wisconsin have been floated.