The Senate Polls Were Wrong. They Favored Democrats By a Significant Margin.

In the runup to the election, a
number of election analysts noted that, despite polls showing a
likely Republican takeover of the Senate, Democrats could perhaps
take hope in the possibility that the polls were wrong,
systematically biased toward the GOP.

In The New Republic, for example, Sam Wang, co-founder
of the Princeton Election Consortium,
wrote in October that “although Republicans have the advantage
in polls, Democrats’ track record of outperforming polls works in
the other direction. For the moment, there’s a decent probability
that polling nerds will be surprised on November 4.” Worried
Democrats could hold out hope that the polls were wrong. “When
errors occur, the outcome tends to be more favorable to the
Democrat,” he wrote. 

As it turns out, the polls were wrong. They
dramatically favored Democrats.

As polling guru Nate Silver
writes at FiveThirtyEight “the pre-election polling averages
(not the FiveThirtyEight forecasts, which also account for other
factors) in the 10 most competitive Senate races had a 6-percentage
point Democratic bias as compared to the votes counted in each
state so far.” (This doesn’t account for Alaska, which takes longer
to report election returns.)

This shows the danger of putting one’s faith in the hope that
polling data is wrong, as many conservatives did in 2012 with Mitt
Romney and as some liberals clearly did this year. Yes, of course,
it could well be wrong. Polling isn’t perfect, and it often misses
important trends. But if it’s possible that the polls are
systematically wrong, then it’s possible that the polls are
systematically wrong in a way that doesn’t favor the party you
favor. And for Democrats, that seems to have been what happened
last night.