McLean County Republican Party Chairman John Parrott says six people have already talked to him about replacing Congressman Tim Johnson on the November ballot. The GOP chairman in the 14 counties that make up the 13th Congressional District will select a candidate to run in the general election against Democrat David Gill.  Parrott says he considers four of the candidates to be in contention for the seat if they choose to run.  They are Johnson's former chief of staff Jerry Clarke, Bloomington State Representative Dan Brady, Rodney Davis, who's an aide to Congressman John Shimkus, and Decatur State Representative Adam Brown.  Parrott says two others have inquired about the post, including Bloomington sports team and restaurant owner Jim Bob Morris and one other person.  Parrott didn't say he's ready to endorse a candidate now, but indicated he would prefer to have someone from McLean County represent the district.  He says he expects the county chairmen will appoint a candidate by mid-May.