Julian Zelizer: Can the Cain Campaign Survive the Sexual Harassment Complaints?

Julian Zelizer is a professor of history and public affairs at Princeton University. He is the author of "Jimmy Carter" (Times Books) and author of the forthcoming book "Governing America" (Princeton University Press).

(CNN) -- Herman Cain, the surprise candidate of 2012, has been struggling to survive accusations of sexual harassment. Every day that the story continues and new accusations emerge, Cain's candidacy is at greater risk.

Yet thus far his polls have remained steady, and the news cycle seems to be turning toward other issues. Cain has denied the accusations and pushed back against the accusers.

Cain is far from the first presidential candidate to struggle with a scandal centered on sex.

Sex scandals have a long tradition in American politics. In the presidential campaigns of 1824 and 1828, opponents accused Andrew Jackson of adultery, while in 1884 Republicans lambasted Grover Cleveland for his illegitimate child. Supporters of Cleveland's opponent, James Blaine, liked to chant "Ma, Ma, where's my pa?" whenever they had a chance.

During the first seven decades of the 20th century, sex scandals played a diminished role on the campaign trail. The news media exhibited remarkable restraint, as reporters stayed within boundaries defining what kind of behavior was appropriate -- or relevant -- to report and what was not. The rules governing behavior at the workplace were also extraordinarily lax, and reporters, like other Americans, didn't expect men to meet a high standard in treating the women around them....