U.S. Rep. Jerry Costello, a Democrat, said in October that he would retire next year after 24 years in Congress. Since Costello’s southwest Illinois district is socially conservative, Republicans smell an opportunity worth spending national GOP money on.

The GOP has already coalesced around Jason Plummer, the 29 year-old former nominee for lieutenant governor who works for his family’s lumber business.

Democrats appear united behind Brad Harriman, the former regional school superintendent for St. Clair County, which is the largest county in the 12th District.

“Republicans will try to nationalize the race and make it about Obama and the economy,” says John Jackson, the former dean of Southern Illinois University in Carbondale and a current political science professor at the school. “Democrats will try to localize it and say that Jerry Costello looked after the district.”

Jackson is skeptical that Republicans will pick up a district that has gone more than six decades with a Democrat – Costello’s predecessor was Democrat Mel Price who served for 42 years.

“The district traditionally leans Democratic,” Jackson says. “Republicans certainly got their message out with Fox News and talk radio – those are popular here.”

“But the area has been traditionally populated by union mineworkers and its still economically liberal,” Jackson adds.

Generally an economical liberal and social conservative, Costello has an unorthodox recent voting record. He voted against the Iraq War. He was also part of a coalition of Congressional Democrats that nearly killed health care reform by demanding more restrictions on abortion.

But constituents may better remember him for securing local money and jobs – like championing the Scott Air Force Base in St. Clair County..

“Costello did a lot non-ideological bring home the bacon sort of stuff,” says Kent Redfield, a political science professor at the University of Illinois-Springfield.

“So,” Redfield adds, “Now what happens here is that you have a beloved long-term conservative Democrat and so when he retires voters might say that, ‘If you’re going to vote conservative, you might as well vote Republican.’”

But will voters take to Plummer?

Plummer is 29 and the vice president for corporate development at R.P. Lumber in Edwardsville, Illinois, which was founded and run by his father, Robert Plummer. He got the GOP nomination for lieutenant governor in 2010.

Plummer has money (and will probably get Republican National Committee cash), but his bio is arguably a little thin for a U.S. Congressman. It includes mentions of internships, like one for the Heritage Foundation, and notes that as an undergrad at the University of Illinois at Champaign, Plummer headed student opposition to a speech by Bill Ayers.

Also, in his run for lieutenant governor, Plummer had a sometimes questionable command of the dire economic and state budget issues facing Illinois.

Both St. Clair and Madison County Republicans are poised to support Plummer. “I feel very strongly that Plummer will get the nomination,” says Deb Detmers, chairman of the Madison County Republican Party. “He’s very energetic and intelligent and ran very strongly in the district in the primary and general election [for lieutenant governor].”

The Democrat, Harriman, is a political unknown and got organized support after several more visible Dems, including Lt. Gov. Sheila Simon, said they wouldn’t run. Harriman was a regional school superintendent until state funding for the position ended in June 2011. A regional superintendent’s duties include teacher certification and monitoring the safety of school buildings.

Robert Sprague, chairman of the St. Clair County Democratic Party, said that the party was supporting him, “Because of his background in education and background in his family being coal miners.”

Matt Melucci, chairman of the Madison County Dems, pointed out regional superintendent was an elected position and that Harriman has spent his life in the district.

“He knows the district,” Melucci says, adding. “These are blue collar working class districts and people are struggling.”

Other Illinois “coal basin” Congressional races could be contested thanks to redistricting. Rep. John Shimkus (R-19), a Republican who has been in office since 1993, claims that about 40 percent of his district’s area changed after state redistricting.

Complicating matters is a GOP-lead lawsuit that may redistrict the state once again before 2012.

Shimkus has pushed extending the Keystone Pipeline System from Canadian oil sands, an idea environmentalists say will destroy fresh water and contribute to global warming.

Image: AP