Peter Berkowitz collects quotes from 2008 saying conservatism in America is over forever.

And:

The credit for galvanizing ordinary people and placing individual freedom and limited government back on the national agenda principally belongs to President Obama, House Speaker Nancy Pelosi and Senate Majority Leader Harry Reid. Their heedless pursuit of progressive transformation reinvigorated a moribund conservative spirit, just as in 1993 and 1994 the Clintons' overreaching on health care sparked a popular uprising resulting in a Republican takeover of Congress.

So it wasn't that conservative principles caught hold of America. It was that the progressives scared the hell out of us.