The strong economy combined with restrained government spending to produce consistent government surpluses, and total federal debt shrank by one quarter during Coolidge's presidency. Coolidge also signed the Immigration Act of 1924, which greatly restricted immigration into the United States. Pennsylvania Governor Gifford Pinchot, a progressive Republican and potential rival for the 1924 presidential nomination, quickly settled the strike with little input from the federal government. Pinchot's settlement of the strike backfired, as he took the blame for rising coal prices, and Coolidge quickly consolidated his power among Republican elites. Potential opponents like Governor Frank Lowden of Illinois and General Leonard Wood failed to generate support for a challenge to Coolidge, while automobile magnate Henry Ford endorsed Coolidge for president in December 1923.The Republican Convention was held on June 10–12, 1924, in Cleveland, Ohio; Coolidge was nominated on the first ballot. Coolidge's nomination made him the second unelected president to win his party's nomination for another term, after Theodore Roosevelt.