The Republicans are bemoaning, and the Democrats celebrating, the third straight Democratic victory in a strong Republican congressional district. Three does make it look like a significant trend. The nature of the trend is debatable. While most pundits are arguing for a change among Republicans of message or viewpoint, I suspect too little is made of effective Democratic tactics. In each case, and in many of the seats the Democrats picked up in 2006, the Democrats ran a candidate who had many conservative aspects, often using a service veteran.
The juxtaposition of the most recent congressional triumph of the Democrats, running a DINO, with a recent Wall Street Journal piece from Pat Toomey defending RINO hunting among Republicans is telling. Either party can ably contest districts more sympathetic to the main message of the other, if they run candidates appropriate to the district. As long as the Republicans shun RINOs and the Democrats woe DINOs the US Congress is likely to remain Democratic.