Special interest groups spent just under $10 million on elections in Wisconsin this year, according to the Government Accountability Board.

The GAB said in a statement Friday high independent spending this election cycle was due partly to a recent U.S Supreme Court decision allowing corporations and unions to spend unchecked money to influence state and federal elections.

After the Citizens United ruling, the GAB adopted new reporting procedures to track campaign spending of corporations and other organizations within Wisconsin.

Of the corporations and labor union spending recorded, the Republican Governor’s Association topped the list with almost $3.5 million in contributions during an election period defined by sweeping Republican victories.

This partisan spending may have been a special interest trend during the 2010 midterm election.

“I do not think there is any question there was a bit more outside money spent on behalf of Republican candidates,” Jay Heck, executive director of Common Cause in Wisconsin, said. “Corporations outnumber unions, and they tend to favor Republicans.”

Congress could also have required corporations to report in the same way as the GAB after the decision, according to Heck.

However, the U.S. Senate adjourned in April before agreeing on terms of disclosure, and as a result these groups were not required to disclose their donors, Heck said.

Heck added in the 2010 election, special interest group spending increased, and most of the ads people were seeing were from corporations and other groups, not political candidates.

While $10 million in special interest spending is high, executive director of the Wisconsin Democracy Campaign Mike McCabe said it may not even be the whole amount.

“What was disclosed and included in the GAB report is more than the tip of the iceberg [of spending in the election],” McCabe said. “However, while there was $10 million dollars in spending disclosed, there were millions more spent but not disclosed.”

The current law requires special interest groups to disclose who they are and how much they spend in elections, but the vast majority of these groups are organized so they do not disclose their donors, McCabe said.

As a result, the level of transparency in the 2010 election was especially poor, McCabe said.