 Lucas was a member of the Virginia House of Delegates in 1838 and 1839 and was elected a Democrat to the United States House of Representatives in 1838, serving from 1839 to 1841 and being unsuccessful for reelection in 1840.He was elected back to the House in 1842, serving again from 1843 to 1845 and once again being unsuccessful for reelection in 1844.Afterwards, Lucas resumed practicing law and engagements in horticultural pursuits and was a delegate to the Virginia Constitutional Convention in 1850 and 1851.