One interesting, but not always precisely reliable, measure of partisan preference is what pollsters call the generic vote -- which party's candidates people would vote for in elections to the House of Representatives. Over the past two decades, responses have tended to underpredict Republicans' performance in subsequent elections, though that was the case more in 1992-2002 than recently. The last two months have seen sharp shifts in the generic vote, as National Journal's Charlie Cook notes, with Democrats peaking during the government shutdown in the first half of October and then a sharp swing to Republicans after the spotlight shifted to the Obamacare rollout. (The Huffington Pollster provides a vivid graphic on this.)

The current RealClearPolitics average of recent polls shows Republicans leading Democrats 43 percent to 41 percent (they actually put it at 43.5 percent to 41 percent, but I prefer to round off to integer percentages and always round the .5 percentages down). I went back to RealClearPolitics' 2010 figures to see how they compared. The answer is that if you average the most recent results available at this stage of the 2010 cycle (using just the most recent result from Rasmussen Reports, which asks the question most frequently, and omitting polls that were in the field on Dec. 6), you find Republicans trailing Democrats 43 percent to 45 percent (43.4 percent to 45 percent, to include the tenths).

Republicans ended up winning the popular vote for the House 52 percent to 45 percent in November 2010, so an initial comparison suggests they are on track to do better in 2014. But I see reasons for caution in reaching such a conclusion. One is that if you exclude the October 2010 result from the Democratic firm PPP, you have both parties tied (at 44.75 percent) at this point in the 2010 cycle. Another is that Republicans were running about even with Democrats in the generic vote from June 2010. That has not been the case this cycle, in which Democrats have been running significantly ahead all year, except in August and September when their margin was smaller and, briefly, nonexistent.

So maybe the Obamacare rollout has been a game-changer, boosting Republicans up to 2010 territory and positioning them perhaps to win the House popular vote by a bigger margin than in 2010. Or the Obamacare rollout has produced a blip for Republicans, which will likely disappear when the rollout problems seem on their way to being solved or other issues replace it in the spotlight. Take you pick.