In the 1964 election, President Johnson carried Minnesota — which tended to favor Republicans prior to the 1974 Watergate Scandal — by a margin of victory that hadn’t been seen in a presidential election in the state since Franklin D. Roosevelt carried the state by a margin of 30.83 percent over Alf Landon in 1936. This margin of victory was aided by the fact that Hubert Humphrey, the state's incumbent US Senator, was on the Democratic ticket for vice president. Nationally, no candidate since James Monroe’s re-election in 1820 had won as great a percentage of the popular vote as did Johnson in 1964, nor has any candidate since 1964.