[thingumbob]

It seems that every poll I see samples Dems in greater numbers than Republicans. Is there a reason for this other than to make Dems look stronger?

You are wise Grasshopper

.....that's exactly what their up ta...

Always look for Likely voters (LV) over Registered voters (RV)in those polls too. Likely voters are a more accurate pulse of what's happening...

Also pay attention to the timing the poll was taken. Weekends traditionally poll Democrats at much higher rates because the Republicans are out doing things on the weekends. If the polls are done during the weekdays the numbers for Obozo and Romney are usually closer.

[MrChips]

Sometimes it goes deeper than R and D. They also oversample women. Easier to hide. The recent PPP poll showing Obummer up +5 in Ohio not only oversampled Dems +4, but also oversampled women +9.