Haralson first served in the Georgia House of Representatives, at age 26, from 1831 to 1832. He was next elected to the Georgia State Senate in 1836, and served from 1837 to 1838.[1] He was commissioned as a major general in the Georgia Militia, 9th Division, in 1838.[1] Haralson was originally a member of the Whig Party, but left when that party advocated for a restoration of the Bank of the United States, something that Haralson was opposed to because of his Jeffersonian leanings.[2] Haralson subsequently joined the Democratic Party and stood for election to Congress under that banner. Despite the fact that Georgia voted overwhelmingly for the Whig party, in 1840, Haralson was elected as a Democrat two years later.[2] Haralson represented Georgia in the U.S. Congress from 1843 to 1851, where he was chairman of the Committee on Military Affairs during the Mexican–American War.[3][4] He was the father-in-law of the famous Confederate General, and Georgia governorJohn B. Gordon.