In Wisconsin, six Republican state senators face recalls on Tuesday. And outside groups have sent enormous sums of money into the state in preparation. Local races rarely receive this much attention or this much out-of-state funding, but both liberal and conservative advocacy groups have decided there’s enough at stake to prompt a tidal wave of outside support.

ABC News reports that non-Wisconsin organizations have poured $25 million into the races so far. That figure came from the nonpartisan Wisconsin Democracy Campaign, which estimates that candidates themselves have added only another $5 million.

“Never has so much money been spent on so few voters,” said Charles Franklin, professor of political science at the University of Wisconsin.

The various parties involved have different motivations, he said.

“For the unions, the national unions, this is the risk of similar policies in other states succeeding, and so there’s a definite stake, material stake for them,” he explained. Franklin notes that the policies Gov. Scott Walker and the Republican legislature targeted and curtailed are “the very life blood of unions.”

“For the pro-Republican and conservative groups, it’s less directly an economic interest, but it is a very powerful interest in the direction of policy making,” he said. For these groups, the question turns on “how much can they rein in state unions, and through that, rein in state spending as well.”

Those are certainly the sentiments of Tea Party Express, one such group which has just concluded a four-day “Restoring Common Sense” tour through Wisconsin in support of the Republican senators who face recall Tuesday.

“This is an important battle in restoring fiscal sanity in the country,” Sal Russo, co-founder of the Tea Party Express, told The Daily Caller in June when the recall elections first kicked off.

He noted then that Tea Party Express, in general, stays out of state issues, but added that “it has become such an important fight that we felt that it was important we participate in it,” so that the resistance to what reforms that he called necessary did not “overshadow the need for reform.”

“The purpose of this tour is to help change the debate,” explained Tea Party Express communications director Levi Russell. “The left has pumped nearly 14 million dollars of frenzied fear mongering into the state, and waged war against the newly elected Governor and State Senators who are trying to balance the budget and keep the state economy on track … We are there to let Wisconsonites who are concerned about the economy know that they are not alone, and they are not wrong, evil, hobbit terrorists as some would have them believe!”

“This election is bigger than Wisconsin and Governor Walker,” emailed Brett Healy, President of the John K. MacIver Institute for Public Policy, a think tank that promotes free markets and limited government.

“They are mobilizing their resources and volunteers from across the country in an all-out attempt to overturn the November elections,” Healy wrote in the email. “If Big Labor does not turn the tide and regain control of the Wisconsin State Senate Tuesday, these common sense fiscal reforms that finally rein in the platinum benefit costs of government employees will certainly spread to other states and municipalities across the country.

“We are already seeing proof in Wisconsin that the collective bargaining changes are saving local governments and taxpayers millions of dollars. … If Big Labor does not stop this fiscal responsibility movement tomorrow, there is no telling how far and wide it will grow.”

“The amount of money the unions have spent has been incredible and unprecedented, some estimates are as high as $20 million dollars,” he added. “If they are successful here, expect the 2012 Presidential election and races across the country to be a carbon copy of the Wisconsin recalls.

For non-union groups on the left like EMILY’s List and Progressive Campaign for Change, Franklin says it’s less about policy and more about “ideology” and “values.”

For these groups, it’s “more the ideological question of liberal versus conservative governance, and it’s also the partisan side of trying to recover from the republican landslide of 2010,” he said.

“Republicans across the country pulled a bait and switch on voters,” EMILY’s List’s communications director Jess McIntosh told TheDC in July. “They campaigned on jobs and then turned around to pursue this radical anti-worker, anti-family agenda. Their overreach in Wisconsin ignited the nation — it energized Democrats everywhere to stand up and fight back.”

Wisconsin’s recall elections will take place on Tuesday, when six Republican state senators face recall. Two Democrats face recall on August 16; a third Democrat state senator already survived a recall in July.