“Democrats’ odds of holding the Senate are declining based on the latest polls. But the race is close. Republicans are counting on narrow leads of just a percentage point or two holding up in some of the most important races, like those in Iowa, Colorado, Georgia and Alaska.
Last month, I examined the possibility that Senate polls could prove to be biased or “skewed” against Democrats. If the polls have even a modest bias against Democrats, the party’s chances of keeping the Senate would be more like 50-50. And if the polls have a more severe anti-Democratic bias, it would be favored to keep its majority.”