Lauzen, who boasts strong support among the conservative base in the district, will be facing wealthy dairy owner Jim Oberweis and Geneva Mayor Kevin Burns in the GOP primary.
The February primary is shaping up to be a battle between organization and money.
Lauzen has served 14 years in the state legislature, and has won re-election in large part because of his dedicated corps of volunteers. But his unstinting brand of conservatism has turned off parts of the GOP establishment, including Hastert.
Oberweis, who ran unsuccessfully for the Senate and for governor, will be able to self-finance his own race. And from his previous campaigns and famous dairy stores, he already has solid name identification in the district.
Burns, considered the most moderate candidate, is the wild card in the race. If Lauzen and Oberweis split the conservative vote, some observers believe Burns could prevail in a three-way primary.