You don't need to look far online to find those that automatically dismiss any poll from PPP to be skewed liberal propaganda. Some even go as far as to claim that they are biased sometimes into the double digits. While you are entitled to your opinion, you cannot just make up your own set of facts. These type of statements call to mind the narrative leading up to the 2012 election saying that all of the polls were a lie and Romney was going to win. Some even said win by a landslide. Well I guess you can ask president Mitt Romney how accurate that narrative was.
In 2012, PPP conducted 71 polls between Obama and Romney and ended with an average error of 2.7%. The average bias of PPP polls in 2012 for President was R +1.6%. The election result was to the left if the "skewed liberal" PPP polls. Now, to be fair, PPP was in fact to the left of much of the 2012 polling. Rasmussen was R +3.7% and Gallup was R +7.2%. So saying that PPP is skewed to the left, is possibly half true. (although misleading)
You may also say: well 2012 was a Presidential year. Democrats turn out at a higher rate in Presidential elections than they do during midterms. Well, yes they do. However, the data from the 2010 Republican wave, does not support that presumption in regards to the accuracy of the polling done by PPP. Well in 2010, PPP's final polls broke down like this representative sample:
Nevada Senate- PPP= R +1% Actual=D +5.65%
Colorado Senate- PPP= R +1% Actual = D +1%
Illinois Senate- PPP= R +4% Actual = R +2%
Pennsylvania Senate- PPP= R +5% Actual=R +2%
West Virginia Senate- PPP= D +5% Actual= D+10%
California Senate- PPP= D+4% Actual= D +9%
Ohio Senate - PPP= R+18% Actual= R +18%
In the majority of the races that PPP polled in both 2010 and 2012, they underestimated the Democratic candidate. Therefore, statistically, when PPP is off, they are off to the right rather than to the left. Saying that a poll showing a dead heat in a particular race from a PPP poll automatically means that the Republican is ahead is intellectually dishonest.