Wisconsin's two candidates for the state Supreme Court have spent more than $1.3 million this year, according to campaign finance reports filed Monday.

Annette Ziegler, a Washington County Circuit Court judge, has spent nearly $200,000 more than her opponent, Madison attorney Linda Clifford, since Jan. 1.

Ziegler reported spending $754,500, and Clifford reported spending $564,900. Combined with previous spending reports, the candidates have spent a total of more than $1.4 million over the course of the entire campaign, which the Wisconsin Democracy Campaign said is a state record by a long shot.

"This should be alarming to any voter of any age," said Mike McCabe, executive director of the Wisconsin Democracy Campaign, a government watchdog group.

"Judicial independence is under assault when you have big special interest groups banking campaigns," McCabe added. "They don't want impartial justice — they want special interest justice."

Late last week, the Wisconsin Democracy Campaign released a report saying outside interest groups have spent more than $1.7 million on "issue advertising" for the state Supreme Court election. McCabe said spending increased to $2 million by Monday afternoon.

"So far they've outspent the candidates," McCabe said. "We've never seen this type of activity."

Early in the election, McCabe predicted candidates and outside interest groups would spend $3 to $5 million this year. Now, he said, it's more likely going to be in the $5 to $6 million range.

"People like students have a particular reason to worry about this because they give the least amount of money to campaigns," McCabe added.

Also — just one week before the April 3 election — retiring state Supreme Court Justice Jon Wilcox announced his endorsement of Ziegler.

Wilcox said Ziegler received his support "primarily based upon on her past record."

"The reason I made the endorsement was because of Judge Ziegler's background and qualifications, and probably because I've been listening to the debates and her judicial philosophy," Wilcox said. "I think, between the two, she is the best candidate — that's my judgment call."

Ziegler called the endorsement to replace Wilcox, who is retiring after 15 years of service, a "great honor."

"He is leaving some very big shoes to fill, but I look forward to the opportunity to follow in his footsteps," Ziegler said in a statement. "I only regret that I will not have the opportunity to serve directly with him."

Wilcox joins three former Supreme Court justices and former Republican Gov. Tommy Thompson as notable political leaders to endorse Ziegler, according to her campaign website judgezieglerforsupremecourt.com.

Clifford has garnered the endorsement of four former Wisconsin governors, several members of the state's congressional delegation and two former state Supreme Court justices, according to her campaign website lindacliffordforjustice.org.