He returned to Nevada after law school and served as Henderson city attorney before being elected to the Nevada Assembly in 1968. In 1970, at age 30, Reid was chosen by O'Callaghan as his running mate for Lieutenant Governor of Nevada. Reid and his mentor O'Callaghan won the race and Reid served as lieutenant governor from 1971 until 1974. Reid became the youngest lieutenant governor in Nevada's history. When he ran for the U.S. Senate seat being vacated by Alan Bible. He lost by fewer than 600 votes to former Governor Paul Laxalt. In 1975, Reid ran for Mayor of Las Vegas and lost to Bill Briare.