Greg Sargent, Political Wire, and others have cited numbers from Public Policy Polling to argue that President Obama's approval ratings among self-identified liberals remain quite high. According to PPP, President Obama's job performance among self-identified liberals is still a robust 85%.
However, there is a serious flaw in citing these numbers: they are only based on a subsample of between 125-130, which gives them a margin of error of plus or minus 8.9%. That is, they are only based on a subsample of 125-130 registered voters if PPP's new national survey is anything like their national survey from last month, when 19% of their overall sample of 667 voters self-identified as liberal.
By way of comparison, across the last four Gallup weekly approval polls, which have a combined sample of 14,346 respondents, President Obama's job performance among self-identified liberals has only averaged 74%. With Gallup identifying 20% of the electorate as liberal so far in 2010, that would mean a liberal subsample of 2,869, that would mean a margin of error of only 1.8%. That makes the Gallup numbers far, far more reliable than the PPP numbers.
Looking across all other job performance polls taken over the past month, only one organization, YouGov, produced crosstabs based strictly on ideological self-identification. There are literally no other polls that released such crosstabs-only PPP, Gallup and YouGov.
Across 899 self-identified liberals surveyed in their last four polls, YouGov's does show President Obama's approval rating at 84%. That number is much closer to PPP's result than to Gallup's. Also, the subsample only has a margin of error of plus or minus 3.3%, which means that random error alone cannot account for the difference between the Gallup and YouGov numbers. Further, both Gallup and YouGov are sampling "all adults," and cell-phone onlys, so the difference cannot be found there either. That YouGov is conducted over the Internet might be causing problems, but Polimetrix, which actually conducts the YouGov polls, actually has a decent track record.
So, where does Obama's approval actually stand among self-identified liberals? While PPP's sample size is too small to be taken seriously, it would be unwise to look for "The One, True Poll," and completely ignore either YouGov or Gallup, both of which have good sample sizes. Personally, I am a big believer in simple poll averaging as a way of providing an accurate snapshot of electoral preference, and the numbers back me up on that belief. I see no reason why simple poll averaging can't be applied in this situation as well, which would peg President Obama's approval rating among self-identified liberals at around 79-80%.
Those are not very good numbers for President Obama among self-identified liberals. However, they are too be expected given his overall approval rating of 44.6%, which is itself not a very good rating. Also, until the Obama administration and Congressional Democrats start passing public policy that has a more immediate, positive impact on the lives of most Americans, it is unlikely that this rating will improve. That is the case no matter the "political reality," and no matter much anyone sneers, or does not sneer, at progressives.