Public Policy Polling Manipulates Sampling - In Favor Of Republicans?

PPP is notorious for oversampling Democrats to yield results that give heart to the left and the news media. Suddenly, PPP turns out a poll surprisingly favorable to a Republican candidate and it seems that they oversampled Republicans. 

Why?

[T]he sample went from D+2 to R+9? Gee, does anyone think that a heavily-Republican sample might be why Akin isn’t trailing yet?

Anyone suspect that the Democrat polling firm might be trying to get the result they want, to ensure Akin stays in, so that he can get pummeled in November?

Thanks to Number-Cruncher for catching this.