At midnight Monday night, Wisconsin Democrats and labor activists kicked off their campaign to recall Gov. Scott Walker (R).

Petitions were also filed to recall the lieutenant governor, Rebecca Kleefisch (R), and three Republican state senators — Pam Galloway, Terry Moulton, and Van Wanggaard.

Depending on whether recall signatures that must be gathered by early January 2012 are deemed valid, the recall would be slated for March 27. If there are primaries on either side, the recall would be delayed to April 24. But delays because of legal challenges are likely and expected.

Wisconsin Gov. Scott Walker talks to the media at the state Capitol in Madison, Wisconsin. (Andy Manis/AP)

In a February vote with national political implications, Republican lawmakers passed and Walker signed legislation that banned collective bargaining for many public employees. After the bill became law, Democrats triggered recalls against six Republican legislators and defeated two. But they fell one vote short of winning back control of the upper chamber.

Taking on Walker himself was always part of their plan, but the governor was not eligible for recall until he had been in office for over a year. After their defeat Democrats vowed to press on, pointing to an analysis from the New York Times’ Nate Silver that based on the state Senate results, a Walker recall would be very close.

Wisconsin has some of the most stringent recall requirements in the country. Organizers have 60 days to gather signatures equal to 25 percent of the total votes in the last gubernatorial election to get a recall on the ballot. That means 540,208 valid signatures must be gathered by Jan.14, 2012 and filed by Jan. 17 to recall Walker and Kleefisch.

For the three state Senate recalls on tap, the signature requirement is 25 percent of the total gubernatorial votes in that district — about 15,000 per senator.

Organizers told the Milwaukee Journal-Sentinel Monday that they hope to gather 600,000 to 700,000 signatures in case some are thrown out. The petitions are being gathered by a political action committee called United Wisconsin.

Once the petitions are filed, the state accountability board has 31 days (until Feb. 17) to review them. If enough signatures are deemed valid, a recall election would be set for March 27. If there are primaries on either side, the recall would be pushed back to April 24.

Democrats are expecting legal challenges to delay the recall past those dates, as happened over in the state Senate races. Republicans are considering again running fake primary candidates to delay the elections.

Democrats were initially leaning towards timing the recall to coincide with the November 2012 general election. But they decided not to wait.

“There was momentum to do it now, people wanted to do it now,” said Wisconsin Democratic Party spokesman Graeme Zielinski. They agreed that given delays, it would be almost impossible to schedule the recall for the November election, and they would squander enthusiasm by waiting.

Democrats also say that launching their campaign now limits Walker’s ability to raise unlimited campaign cash.

A Walker supporter launched a recall campaign of his own on Nov. 4 — “Close Friends to Recall Walker.” Under Wisconsin law, when a politician faces a recall campaign, contribution limits don’t apply. Democrats argue that such a gambit was inevitable, and that by starting early they limited Walker’s fundraising window.

Walker has already begun airing ads defending his record. The next few months will be an intense fight.

In American history, only two governors have ever been successfully recalled: California Gov. Gray Davis (D) in 2003 and North Dakota Gov. Lynn Frazier (R-Nonpartisan League) in 1921.

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