By John Dodge

CHICAGO (CBS) — The Illinois Primary is Tuesday, March 18. Here are some of the key races to watch:

GOP Governor

Millionaire businessman Bruce Rauner is competing against three veteran politicians: State Sen. Kirk Dillard, State Sen. Bill Brady and State Treasurer Dan Rutherford.

Rauner has pumped up to $50 million into his campaign, including a massive broadcast ad buy. Brady edged Dillard in the 2010 GOP Primary, but lost a close race to Gov. Pat Quinn.

All four candidates have spent time blasting Quinn on the state’s money woes, high taxes and unemployment.

They have been positioning themselves as the best candidate to bring businesses to Illinois and create jobs, either through a series of tax code changes and other incentives that they say would lower the cost of doing business in the state.

The winner will face Quinn, who is facing token opposition from Tio Hardiman, in the November General Election.

GOP U.S. Senate

State Sen. Jim Oberweis and Doug Truax square off for a shot against U.S. Sen. Dick Durbin in November.

Oberweis, who is leading in the polls, had to defend a recent trip to Florida, just a few days before the primary.

He traveled there to celebrate his wife’s birthday. She had been staying at the couple’s Florida residence. The trip brought up questions from his opponent about the Oberweis’ main residency and his commitment to the state.

Traux is a business owner and graduate of West Point. He has accused Oberweis of ducking him and refusing to debate.

Democrat State House, 39th District

State Rep. Toni Berrios is the daughter Cook County Democratic Party Chairman and Assessor Joe Berrios, considered one of the most powerful Hispanic pols in the state.

Challenger Will Guzzardi, who is from New York and lives in Logan Square, is trying for the second time to unseat Berrios.

Both candidates have strong political support. Berrios is backed by powerful House Speaker Mike Madigan, while Guzzardi has the support of the Chicago Teachers’ Union.

Democrat State House, 26th District

State Rep. Christian Mitchell has been endorsed by every major Democratic politician in the state, including Gov. Quinn, Durbin, Chicago Mayor Rahm Emanuel and Attorney General Lisa Madigan.

The Chicago Teachers Union, however, has endorsed his opponent, Jay Travis, because of Mitchell’s support for charter schools.

That dynamic has resulted in tens of thousands of dollars in attack campaign ads launched by both sides, according to an analysis by the Hyde Park Herald.

The Herald breaks down the facts in several ads here.

Democrat State House, 10th District

Four candidates are trying to unseat incumbent Derrick Smith, who is facing federal bribery charges.

U.S. Rep. Danny Davis and the Chicago Tribune have endorsed Pamela Reaves-Harris. The other candidates are Antwan Hampton, Beverly Petreet and Eddie Winters.

Smith was indicted in March 2012 and was expelled by fellow House members. However, he won the seat in the November election and his running for another term.

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