New York Mayors Can't Woo the Nation - Room for Debate - NYTimes.com

"The last time a New York City mayor sought and got a higher office was in 1913 when the Republican acting mayor, Ardolph Loges Kline, successfully ran for Congress. In 1971, John V. Lindsay switched parties and made a short bid for the Democratic presidential nomination. In 2008, Rudolph Giuliani made a bid for the Republican nomination. He lost, and although he’s toyed with running for governor or senator, hasn’t."