LA CROSSE, Wis. -- A record amount of money has been spent already on Wisconsin’s gubernatorial recall election, with out-of-state donations leading the way.

We've already seen $40 million to $45 million spent on this race so far. That makes it the most expensive state election in Wisconsin's history.

It's also takes the cake for the most outside money flooding in. Non-Wisconsin donors are pouring money into this race, seeing it as an indication of where the rest of the country may go, especially when it comes to union rights.

"The amounts are just astronomical by any standard. It's very rare that you get outside money in a state race, at least substantial amounts," said UW-L Political professor Joe Heim.

That's because national interests are seeing what's happening in Wisconsin and wondering what the outcome of the recall election will mean for them.

“This recall election has become something of a national referendum. And there are interests across this country that I think really see Wisconsin as a domino, and they want to make sure that that domino falls in a way that favors them. Because I think that they figure that domino will knock over a lot of other dominoes," said Mike McCabe, the director of the Wisconsin Democracy Campaign.

So where are the candidates getting their money?

Let's start with Gov. Scott Walker. He's raised $25,350,775.80. It's the most any candidate for any state office has ever raised. According to the Wisconsin Democracy Campaign, 60 percent of that money is coming from outside the state.

Walker said he's raising out of state money in response to the out-of-state donors on the other side.

"A good chunk of it came because people saw how much was coming in over the past 15 months from out-of-state special interests to attack us, so people across the state and, in many cases, across America, said that they were going to help us counter that," said Walker.

Heim doesn't buy it.

"Frankly, most of the outside money is coming to Scott Walker,” said Heim. “But don't underestimate the fact that labor is also involved ... They see this as a life and death struggle."

So let's take a look at the governor's Democratic challengers.

Kathleen Falk raised $1,018,600.25. About 46 percent of that money came from outside Wisconsin.

Tom Barrett raised $831,508.41. About 13 percent of his cash came from out of state.

Doug La Follette and Kathleen Vinehout both received a sprinkling of contributions from out-of-state. La Follette reported raising $118,087.55, but about $112,000 of that was his own money. Vinehout raised $93,998.33 -- mostly from individual contributions.

But Heim said this money is just the beginning.

"Some Democrats are holding back until they know who their candidate is. They really want to get more bang for their buck. So I would expect a lot of Democratic givers to wait until the primary is over with and then give," said Heim.

This is just the money that’s been reported so far. Candidates have only turned in campaign finance reports for donations through April 23. All of the candidates will have to turn in another report at the end of this month.

Since Nov. 4, Walker has been allowed to collect unlimited contributions to respond to the recall.

The group that organized the petition drive was allowed to accept unlimited donations, but the challengers have not been allowed to do that.