Despite many public and presumably even more numerous private instances of infidelity, presidential marriages have remained remarkably stable throughout history. America has only had one divorcee president, but two widower presidents moved on to second wives while in office. And one president never got married at all.

Ronald Reagan was the only president who ever divorced his wife. But he left that first marriage so early in life, and moved on to such a stable and functional second marriage, that the voters didn't care, said Michael Nelson, a professor of political science at Rhodes College and coauthor of The American Presidency: Origins and Development, 17762007 (CQ Press, 2007). Some presidents, like Franklin Roosevelt, faced the possibility of divorce after their wife discovered an affair , but kept the marriage together for the sake of their political career, Nelson said.

A president, or someone who wants to be president, has every reason to do whatever it takes to keep his wife from divorcing him, Nelson told Life's Little Mysteries. The political price of divorce, where he was the guilty party, even today, would be significant.

The Clintons displayed the political power of avoiding divorce, Nelson said. Had Hillary Clinton not stood by her husband after the public learned of his affair with Monica Lewinsky, President Clinton would have likely faced removal from office or forced resignation, Nelson said.

However, that does not mean that every president has remained in the same marriage throughout their lives. John Tyler and Woodrow Wilson both lost their wives during their presidency, and remarried during their term, Nelson said.

Only one president, James Buchanan, remained a bachelor for his entire life, Nelson said. But he had a good reason for not marrying.

James Buchanan was unmarried at the time he was in office, and is widely thought of to have been what we would today call gay, Nelson said.

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