Greg Sargent reported yesterday that Democrats in Wisconsin plan to file more than 30,000 signatures to recall Alberta Darling, who would become the fifth of the “Republican 8″ state Senators to have recall petitions filed against them.

Graeme Zielinski, the spokesman for the Wisconsin Democratic Party, confirms to me that Democrats will submit approximately 30,000 signatures for the recall of Alberta Darling — nearly 150 percent of the 20,343 required.

This is the fifth time Dems have collected far more signatures than necessary for a recall — all but ensuring that all five recall elections will actually happen.

As Eric Kleefeld notes, Darling is the co-chair of the Joint Finance Committee, the committee that passed out the anti-union “budget repair bill” initially, so she is a high-profile target. The Milwaukee Journal-Sentinel notes that Darling’s district, in the northern suburbs of Milwaukee, voted 54% for Scott Walker in 2010, though they also voted 51-47 for Barack Obama in 2008.

But activists have actually been gearing up for the Darling seat for quite a while. Not just because she has that high-profile position as chair of the Joint Finance Committee, but because they think they have a candidate waiting in the wings strong enough to beat her. In my Wisconsin strategy memo written after my visit to Madison, I touch on this:

One particular recall battle stands out, and progressives may take it on first. Sen. Alberta Darling is the co-chair of the Joint Finance Committee, which reported out the budget repair bill. She represents a North Shore suburban Milwaukee district, which is heavily Jewish and fairly Democratic. It’s the kind of seat many Democrats lost in 2010. In 2011 in Wisconsin, there’s already a candidate lined up for the recall, former Assemblyman Sheldon Wasserman. “This will be a critical contest,” said (John) Nichols. “There’s our referendum.”

In the Daily Kos poll, the only polling done on this race so far, Darling had a 52-44 lead over a generic challenger. But this may be a case where the specific candidate outpolls a generic one. The locals think this is a very winnable race, and the fact that 30,000 signatures were collected to recall Darling is a pretty good sign.

Republicans look ready to file petitions in at least one race against a Senate Democrat, Jim Holperin, today. It’s unclear that they will get more than that done with less than a week to go until the deadline.

UPDATE: Republicans just filed a petition with 18,870 signatures to recall Democrat Dave Hansen. According to this chart, that doesn’t leave them much of a cushion in case some of the signatures are invalidated, though probably enough. They need 13,852 valid signatures to trigger the recall.