Ramesh Ponnuru has a post over at the Corner about McCain's seeming willingness—per his ABC News interview—to raise Social Security taxes.
My take: I know of no political analyst who thinks a President McCain could fix Social Security with a Democratic Congress without agreeing to higher taxes as part of the deal. Even McCain points to the tax-hiking Greenspan Commission of the 1980s as a model of bipartisanship. And McCain has in the past gone on the record in favor of just such a compromise. Maybe because a McCain win would be such an upset, he would come into office with amazing momentum and impose his will on stunned Democrats. Maybe.