Michael Dean Crapo is an American lawyer and politician serving as the senior United States senator from Idaho, a seat he has held since 1999. A member of the Republican Party, Crapo served as the U.S. representative for Idaho's 2nd congressional district from 1993 to 1999. He is the dean of Idaho's congressional delegation, having served since 1993.

Idaho's 2nd congressional district is one of two congressional districts in the U.S. state of Idaho, in the eastern portion of the state. Beginning with the 2012 election, the district expanded westward and now includes most of Boise, the state capital and largest city. The district is currently represented by Mike Simpson, a Republican of Idaho Falls. A former dentist in Blackfoot, he was first elected in 1998; the seat opened when his predecessor Mike Crapo successfully ran for the U.S. Senate.