While certainly Democrats share plenty of blame for our current mortgage mess, let's not pretend that Republicans can claim innocence.  Radley Balko points out these 2002 remarks to HUD from the White House archives by George W. Bush himself:

We are here in Washington, D.C. to address problems. So I’ve set this goal for the country. We want 5.5 million more homeowners by 2010 - million more minority homeowners by 2010. (Applause.) Five-and-a-half million families by 2010 will own a home. That is our goal. It is a realistic goal. But it’s going to mean we’re going to have to work hard to achieve the goal, all of us. And by all of us, I mean not only the federal government, but the private sector, as well.
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And so what are the barriers that we can deal with here in Washington? Well, probably the single barrier to first-time homeownership is high down payments. People take a look at the down payment, they say that's too high, I'm not buying. They may have the desire to buy, but they don't have the wherewithal to handle the down payment. We can deal with that. And so I've asked Congress to fully fund an American Dream down payment fund which will help a low-income family to qualify to buy, to buy.
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And so, therefore, I've called -- yesterday, I called upon the private sector to help us and help the home buyers. We need more capital in the private markets for first-time, low-income buyers. And I'm proud to report that Fannie Mae has heard the call and, as I understand, it's about $440 billion over a period of time. They've used their influence to create that much capital available for the type of home buyer we're talking about here. It's in their charter; it now needs to be implemented. Freddie Mac is interested in helping. I appreciate both of those agencies providing the underpinnings of good capital.

Both Democrats and Republicans used "affordable housing" as a weapon to win votes over the years with little consideration given to the consequences of the market distortions that widespread government intervention causes.  When it works out, everyone scrambles to take credit, and when it goes wrong, everyone works as hard as possible to shift the blame.  But as Fred points out correctly, they are all to blame... all 545 of them.

The ones who made the mistakes that caused all of this are now the ones who are creating the "solutions".  But when their original plans were so bad, why should we trust their solutions?  Both parties have become so drunk for power, and so arrogant in the supposed brilliance of government regulation and planning, that they can't see that the only solution is to stop intervening, because intervention only makes things worse.

We need someone at the helm of this country who will truly put a brakes on the out of control government.  We need Bob Barr.