There is more to the Indiana Senate race between Rep. Joe Donnelly (D-Ind.) and State Treasurer Richard Mourdock than meets the eye.

The contest will also be a rematch between Donnelly and his past House competitor, Mourdock backer and former Indiana Rep. Chris Chocola (R). In 2004, Donnelly challenged then-incumbent Chocola for his U.S. House seat. Chocola won the race with 54 percent of the vote. But in 2006, Donnelly tried again and emerged victorious. Donnelly has successfully defended his House seat over the past two election cycles.

Chocola currently serves as president of the conservative Club For Growth, which supported Mourdock in the Republican primary against six-term incumbent Richard Lugar. The organization has spent $517,691 on Mourdock's campaign so far, according to the Center for Responsive Politics.

“We were opponents in two races, and they were both tough races,” Donnelly told the Journal Gazette of his past competition with Chocola. “I never at any time since I’ve been in Congress ever went back and criticized any of his decisions or the way he ran the office or anything like that.”

Chocola also said that his history with Donnelly has very little to do with the 2012 race.

“It’s all about who is the best candidate to support a pro-economic growth agenda and who’s going to help change the culture of the Senate," he said.

10 more election stories from beyond the presidential field:

Senate Candidate Mark Neumann (R-Wis.) Reveals A Hidden Skill [Journal Sentinel]

New California Election Laws Force Candidates To Engage In Friendly Fire [LA Times]

Rehberg Supports Campaign-Spending Disclosure In Principle, Tester Legislates On It [Billings Gazette]

Rep. Rangel (D-N.Y.) Holds Onto Victory Over State Senator Espaillat [New York Daily News]

John Gregg (D-Ind.) Advocates For Increased Child Welfare While Campaigning For Governor [Indy Star]

Texas GOP U.S. Senate Candidates Still Competing For Conservative Vote [Houston Chronicle]

California Sen. Feinstein Holds 19-Point Lead Over Challenger [San Francisco Chronicle]

Obermueller Raises $250K And Receives Support From DCCC; An Uphill Fight Still Remains [Minnesota Star Tribune]

Tea Party Throws Its Weight Behind Gary Glenn In Michigan U.S. Senate Race [Midland Daily News]

Ads Begin In Connecticut U.S. Senate Race Between Murphy and Bysiewicz [Hartford Courant]

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