At least that's what Bush said back in 1978, according to USA Today (and picked up on by Josh Marshall)
According to a July 28th, 2000 article in USA Today, back in 1978 when President Bush was running for congress in Texas, "he predicted Social Security would go broke in 10 years and said the system should give people 'the chance to invest money the way they feel' is best."
As Marshall points out, you can't just Google news from 1978. But there IS Microfilm of the Plainview Daily Herald available somewhere (Heck, it might be available in the New York Public Library, let alone Plainview, TX). So some intrepid Texan should dig up that microfilm. Because if that statement is accurate, it can be used to beat Bush until he squeals.