 Holt was also only the second research physicist to be elected to Congress, and the first physicist to be elected as a Democrat; he joined Vern Ehlers (R-MI) and was later joined by Bill Foster (D-IL).Foster is currently the only research physicist in the U.S. House of Representatives with the retirement of Ehlers, and Foster defeating Judy Biggert in 2012 to reenter the House.Holt's supporters produced green bumper stickers reading "My Congressman IS a rocket scientist!