Lucas was born January 6, 1960 in Cheyenne (Roger Mills County), Oklahoma. He graduated from Oklahoma State University in 1982 with a degree in Agricultural Economics. He first ran for the Oklahoma house of Representatives in 1984 as a Republican against the incumbent Democrat, narrowly losing. A second attempt in 1986 also fell short, but he won in 1988. Immediately after being seated, Lucas became very vocal for causes he supported, and the Democratic-controlled state house responded by redrawing his district in 1990 in such a way that ensured defeat. Lucas immediately began knocking on doors in his new district and was reelected in 1992.

In 1994 6th District Congressman Glenn English stepped down to become a lobbyist for rural electric cooperatives. Lucas won the Republican nomination for the special election on May 10. He faced Dan Webber, press secretary to former Oklahoma governor and U.S. Senator David Boren, now president of the University of Oklahoma. The 6th was already the largest in the state, stretching from the Panhandle to the town of Spencer, in the far northeastern Oklahoma City metropolitan area. However, the state legislature had redrawn it so that it included many poor Oklahoma City neighborhoods that had never voted Republican. Lucas scored a major upset; he won by eight points, carrying 18 of the district's 24 counties. His victory has been seen by some pundits as an early sign of the wave six months later that saw the Republicans take control of the House for the first time in 40 years. Lucas himself won a full term in that wave and has been reelected five times, never dropping below 59 percent of the vote. He faced no Democratic opposition in 2002 and 2004.

His district was renumbered the 3rd after Oklahoma lost a congressional district in the 2000 census, and now covers as much land as the other four districts combined.