Since Andrew did not resemble either of his siblings, there are rumors that he may have been fathered by another man. Polly Johnson eventually remarried to a man named Turner Doughtry, who was as poor as she was.Johnson's mother apprenticed her son William to a tailor, James Selby. Although a fellow Tennessee Democrat, James K. Polk, was elected president in 1844, and Johnson had campaigned for him, the two men had difficult relations, and President Polk refused some of his patronage suggestions.Johnson believed, as did many Southern Democrats, that the Constitution protected private property, including slaves, and thus prohibited the federal and state governments from abolishing slavery. He won a second term in 1845 against William G. Brownlow, presenting himself as the defender of the poor against the aristocracy. In his second term, Johnson supported the Polk administration's decision to fight the Mexican War, seen by some Northerners as an attempt to gain territory to expand slavery westward, and opposed the Wilmot Proviso, a proposal to ban slavery in any territory gained from Mexico.