The majority of loans made during the bubble were made by institutions not covered by the CRA. Investment banks, hedge funds, pure mortgage lenders, anyone not a deposit taker was free to do exactly as they pleased and they were in the non-conforming subprime market because it was extremely profitable.
While many say that, the "Bush-fault" idea is still controversial:
Considering how the left is beginning this all over again now (Obama Justice Department Forces Banks to Make Risky Loans) mho is that it's definitely now "all Bush's fault".