Ever since Wisconsin Dems and labor activists announced late Friday that they had already amassed enough signatures to trigger a recall election against GOP state Senator Dan Kapanke — and filed their petition to make it happen — political observers have been wondering precisely how many signatures activists had gathered. The number could contain clues as to whether the election will actually happen and how much grassroots energy there remains on the ground in the state.

I’ve now been given the precise number by Wisconsin Democratic Party spokesman Graeme Zielinski, and it’s eye-opening: In that district, 15,588 signatures are needed to trigger a recall — and activists collected and filed a whopping total of 22,561.

That’s 145 percent of the total required — and Wisconsin election experts tell me it virtually ensures that a recall election will take place despite any challenges to the veracity of signatures.

Because the news of the petition broke late on a Friday, the signficance of it has gone entirely unnoticed. Dems and labor activists in the state collected nearly 23,000 signatures in Kapanke’s districts in 29 days — less than half the 60 alloted — which has tied the record for the fastest collection of signatures for a recall election in recent Wisconsin state history. And unlike in that previous case, recall drives are now simultaneously proceeding against other Republicans.

There have been only two successful recalls of state legislators in Wisconsin history, against former state senators George Petak in 1996 and against Gary George for corruption in 2003. George was subsequently convicted on felony charges. In the first case, the requisite signatures were filed on the last day of the 60-day period, according to Nexis, and in the second it took 29 days. In other words, Dems and labor racked up the signatures required against Kapanke as fast as organizers did against a legislator later convicted of a felony.

Wisconsin experts tell me that the number of signatures is a reliable indicator that grassroots energy on the ground remains strong. “Given how long you have to get the signatures and how quickly they got these, it’s a strong signal that the activation of the pro-recall forces is very high,” Charles Franklin, a professor of political science at the University of Wisconsin in Madison, tells me. “Kapanke is in the most Democratic leaning district, but completing a third more than rquired in 20-something days is quite a feat for any petition drive.”

Adds his fellow professor Barry Burden: “I would say it’s a near certainty that they have enough signatures to make the recall go forward.”

The question remains whether the drive on display in Kapanke’s district will manifest itself with similarly strong recall signature showings in other districts. But that said, even though the national press has moved on from this story, the energy and staying power of what has been unleashed in Wisconsin continue to surprise.