Democrats and their allies in organized labor say they delivered over a million recall petition signatures against Gov. Scott Walker (R) Tuesday, far more than the 540,208 needed to spark a recall election.

The filing kicks off the latest phase in a fight over collective bargaining rights that began almost as soon as Walker took office last January.

Democrats also filed 845,000 signatures to trigger a recall against Lt. Gov. Rebecca Kleefisch (R) and enough to recall four Republican state senators, according to party chairman Mike Tate.

Last summer, Democrats attempted to win back control of the state Senate after the Republican leadership passed legislation limiting public workers’ bargaining rights. They recalled two Republicans but fell one seat short of flipping the chamber.

But Democrats and unions pressed on against Walker, who was not eligible for recall until this year. According to the New York Times’ Nate Silver, if last summer’s recalls had been a statewide vote, the results would have been too close to call.

Wisconsin Gov. Scott Walker (R) walks away after addressing the media at the Capitol. (Andy Manis/AP)

Anti-Walker activists needed a substantial signature buffer, because some signatures will almost certainly be thrown out by the Government Accountability Board. Collecting double the required amount, however, is a symbolic gesture. Democrats pointed out to reporters at a news conference in Wisconsin that Walker was elected with only 1.1 million votes.

“We had no doubt the Democrats would be able to rally their left-wing supporters around this baseless and expensive recall effort,” said Republican Party of Wisconsin Chairman Brad Courtney. The Democratic Governors Association “plans to work with our allies to field a candidate,” according to chairman Martin O’Malley, the governor of Maryland.

Walker himself was in New York Tuesday for a fundraiser, but he told a local radio station that the recall was “baseless.” The Republican Governors Association has launched a website in support.

While the petition numbers are impressive, Democrats concede that the actual election will likely be extremely close. If Walker is forced from office, it will be the third successful gubernatorial recall in history.

New requirements mean that verifying the signatures will take at least two months. The election date will then be set for this spring, barring further legal challenges.