Question: What candidate of the United States Senate election in Iowa, 1998 is the current chairman of the Judiciary Committee of the 115th congress?
Sentence (from "United States Senate election in Iowa, 1998"): Incumbent Republican United States Senator Chuck Grassley sought re-election to a fourth term in the United States Senate, facing off against former State Representative David Osterberg, who won the Democratic nomination unopposed.
Relevant evidence: Yes