Here it is mentioned in a Washington Post article. I have other sources, but it is not in dispute, so all sources agree on the fact.
http://www.washingtonpost.com/wp-dyn/content/article/2007/12/21/AR2007122101415.html
“First, there are women, who used to vote disproportionately Republican. (In 1960, for instance, women backed the Republican Richard M. Nixon, with his 5 o’clock shadow, over the dashing Democrat John F. Kennedy.)”
Do you believe everything you read in the Washington Post?
I usually insert a negative into any sentence I read there, in order to see the truth.