I know the impeachment happened in 1998, but my point remains; Gingrich's attempt at ruining Clinton only served to make Clinton more endearing to the public.
And Congress might always have lower numbers than the President, but Gingrich never had an approval rating above 50% during his entire tenure as Speaker and had a disproval rating during the government shutdown that was well into the sixties. Watch the Republicans try to sweep those numbers under the carpet.
Near 50% approval ratings are fantastic for any member of congress. His negatives during the shutdown were never as bad as Clinton's. Anyway, Gingrich has some work to do. And if he introduces a clear and concise (and workable) plan to get this economy back on track he has a shot at winning.