Rush Dew Holt, Jr., PhD (born October 15, 1948) is the U.S. Representative for New Jersey's 12th congressional district. He is a member of the Democratic Party. He is currently the only Quaker in Congress.

Rush D. Holt was born to Rush D. Holt Sr., who served as a United States Senator from West Virginia (1935–1941), and his wife Helen Holt, the first woman to be appointed West Virginia Secretary of State (1957–1959). Holt Sr. was the youngest person ever to be popularly elected to the U.S. Senate, at age 29. He died of cancer when Rush was six years old.

Holt graduated from the Landon School in Bethesda, MD in 1966, then later graduated with a B.A. in physics from Carleton College in Minnesota, and later received his M.A. and Ph.D. degrees in physics from New York University. The title of his doctoral dissertation was "Calcium absorption lines and solar activity: a systematic program of observations".

Holt was a faculty member at Swarthmore College from 1980 to 1988 where he taught physics, public policy, and religion courses. During that time, he also worked as a Congressional Science Fellow for U.S. Representative Bob Edgar of Pennsylvania. From 1987 until 1989, Holt headed the Nuclear and Scientific Division of the Office of Strategic Forces at the U.S. Department of State.