But even in the race's eleventh hour, strategists in both parties are struggling to figure out whether turnout will be closer to 2008 levels, when nearly 70% of eligible Wisconsin voters participated in the presidential election, or 2010, when voter turnout dropped to 49%.

Democrats are hoping for the 2008 model. Almost 3 million people voted in that election, and the state went heavily for Barack Obama.

"It was a low turnout in 2010 and a high turnout in 2008," said former Wisconsin Sen. Russ Feingold, who spent Monday traveling the state rallying Democrats. "If we get anywhere near 2008 or even halfway there, we are going to win, because those folks are more likely to vote for Tom Barrett."

But unlike 2008, when Republican turnout underwhelmed, Wisconsin voters on both sides are now engaged at a level not seen in recent memory.

"We have an example of Hatfields and McCoys going on in this state like we have never seen," said Brian Nemoir, a Milwaukee-based Republican strategist. "People are hyper-engaged, as much in support for their own candidate as in disgust for the opponent."

Handmade signs are nearly as prevalent as official ones. Some locals say they have resorted to lowering their voices in public when discussing the recall to avoid setting off arguments with strangers.

The Marquette University poll revealed that 26% of all voters have slapped a bumper sticker on their car or planted a sign in their lawn.

The same survey found that a third of voters have simply stopped talking politics with someone they know because the race is so heated.

And this is all in a state with a historical reputation for collegiality and Midwestern politeness.

A flood of campaign money, much of it from out-of-state interest groups and most of it benefiting Republicans, is partially responsible for the hothouse political climate.

About $64 million has been spent on the race since November 2011, an analysis from the Center for Public Integrity found.

That's a new state record, shattering the previous record of $37.4 million spent during the 2010 governor's race.

Beginning last fall, Walker seized on a loophole in Wisconsin law that allows incumbents in recall elections to raise unlimited sums.

Walker outraised his opponent by an almost 8-1 margin, collecting $30.5 million to Barrett's $4 million.

Roughly two-thirds of Walker's contributions came from out of state, the Center for Public Integrity reported, while only a quarter of Barrett's funds originated from outside Wisconsin.

Beyond the individual campaigns, independent groups have played a major role in the race, helping saturate television and radio airwaves with negative advertising.

The Republican Governors Association, for instance, has spent more than $8 million on Walker's behalf, most it on television ads.

Working against Walker are unions like AFSCME, the American Federation of Teachers, the National Education Association and the Service Employees International Union, which have also steered millions of dollars to the state in their efforts to unseat the governor.