A new PPP poll should encourage Dems to get mobilized to win back a majority in the House of Representatives in 2014. The findings, as reported in a HuffPo summary:

A series of polls released Sunday show just how damaging the shutdown has been for the GOP. The liberal-leaning Public Policy Polling compiled two dozen surveys, commissioned and paid for by MoveOn.org Political Action, from House districts around the country, taken from Oct. 2 through Oct. 4. Sample sizes were between 600 and 700 voters in each district.
For Democrats to win a House majority, 17 seats would need to switch to their party’s favor. Results show that would be within reach, as Republican incumbents are behind in 17 of the districts analyzed: CA-31, CO-06, FL-02, FL-10, FL-13, IA-03, IA-04, IL-13, KY-06, MI-01, MI-07, MI-11, NY-19, OH-14, PA-07, PA-08, WI-07. In four districts, the incumbent Republican fell behind after respondents were told their representative supported the government shutdown: CA-10, NY-11, NY-23, VA-02. Three districts saw GOP incumbents maintain their hold over their Democratic challengers, even after hearing their elected officials’ views on the shutdown, including CA-21, NV-03 and OH-06.

There are caveats, as always. The poll was liberal-commissioned, with relatively small samples for each of the districts. The election is still 13 months away. The margins were m.o.e. to small in many of the districts.
Still, Dems ahead of incumbents in 17 of 24 districts surveyed should give GOP realists some reason for concern. If other polls begin confirming the trend, then Dems and progressive supporters should up their game in the few swing districts remaining, and put more resources into their candidates. And if the trend is affirmed, that should also open up some senate races in favor of Democratic incumbents and candidates.
To see an excellent chart distilling the findings for each congressional district, click here.