He ran against a Republican who is known mostly for losing big statewide elections five times and who was forced into a punishing runoff for the GOP nomination.
The circumstances of this election cannot be used to support Gingrich's thesis.
I know it is long and winded, but a vote for a Democrat anywhere just serves to empower the ultra-leftists who actually dictate policy now. How are all those "pro-life, pro-2A, and pro-troop" "blue dog" Democrats working out? Not very well!
I think so-called Special Elections are attractive for the opposition party. They are usually brought about by death or some other unusual circumstance that leaves the incumbent party short a real candidate. Often the Out Party has the only ready candidate that they can throw-in, plus a real incentive to heavily fund. I suspect that the R’s might take a beating in the Fall Congressional Elections, but that will depend a lot on how well McCain runs, not some half-*ssed extrapolation from 2 special elections.