CHICAGO (AP) – Illinois’ youngest state lawmaker won the chance to go to Congress. Businessman Jim Oberweis got a shot to make up for past election losses. And perennial incumbent targets geared up for fall contests.

Congressional primaries shook out Tuesday as Republicans picked candidates to defend three open House seats in November against Democrats looking to beef up their numbers in Congress.

This year marks a dramatic shift for Illinois with the retirements of former House Speaker Dennis Hastert and Reps. Jerry Weller and Ray LaHood — all of them longtime Republican congressmen.

State GOP lawmaker Aaron Schock, 26, won the GOP primary to replace LaHood; wealthy businessman Jim Oberweis earned a shot at Hastert’s job; and a suburban Chicago police chief, Timothy Baldermann, got the nod to face a well-known Democratic state lawmaker for Weller’s spot.

Two House Democrats — Reps. Melissa Bean and Daniel Lipinski — fended off primary challengers amid claims they were vulnerable now and in the fall election.

Democrats also decided who will face GOP Reps. Mark Kirk and Peter Roskam this fall. Kirk was in a close race two years ago, while Roskam is a freshman who won one of the hottest races of 2006.

In one of the tightest races of the night, Republicans and Democrats alike dueled for the chance to fill the remainder Hastert’s term and then replace him next year. GOP voters picked Oberweis as their nominee in a March special election to fill the rest of Hastert’s term and to run this fall to replace him beginning next January.

Oberweis has suffered primary losses before for the U.S. Senate and Illinois governor.

“Celebrate tonight, and get a good night’s sleep, because tomorrow the work begins again — and if we do our jobs right, we’ll be right back here in 32 days to celebrate,” Oberweis said in a statement.

The Democratic race in the general primary was too close to call early Wednesday with businessman Bill Foster leading carpenter John Laesch by just more than 300 votes with all precincts reporting. Laesch said he hoped absentee ballots or the official canvass would give him a win.

Foster did capture the special primary over Laesch, setting up a battle against Oberweis next month to fill the remainder of Hastert’s term, which ends in January 2009.