Here's an interesting takeaway from the exit polls: Democratic candidates for Congress won more votes from self-described moderates than they did from liberals. Meanwhile, Republicans swept to victory on a coalition dominated by conservatives -- two out of every three ballots cast for a GOP candidate on Tuesday was cast by a self-described conservative.
Here's a look at the numbers in graphic form:
In 2006, exit polls showed that 55% of Republicans votes came from conservatives. In 2010, that grew to 66%. At the same time, moderates shrunk from 40% to 31% of their coalition and liberals shrunk from 5% to 3%.
On the other side of the aisle, 47% of Democratic votes came from moderates, down from 54% in 2006. 40% came from liberals, up from 33%. And 13% came from conservatives, up from 12% in 2006.
Overall, Democrats won 55% of the moderate vote compared to 42% for Republicans, down from a 60%/38% split in 2006. Perhaps more significantly, as a share of the electorate, in 2010 moderate turnout dropped significantly while conservative turnout soared. In 2006, 32% of voters were conservative; that number jumped to 41%. Also in 2006, moderates were 47% of voters, dropping to 39% in 2010. Liberals stayed constant at 20%.
Obviously one of the key questions here is why moderates were less likely to vote for Democrats in 2010 than they were in 2006. The exit polls can't fully answer that question, but given the sharp decline in moderate turnout, it seems likely that the biggest reason is that Democratic-leaning moderates simply didn't vote.
It's unlikely that moderates were simply renaming themselves as conservatives; if that had happened, you wouldn't have seen a sharp decline in the share of the electorate who voted for Obama in 2008. (Obama voters were 53% of the electorate in 2008 but just 45% in 2010. Liberals dropped from 22% in 2008 to 20% in 2010, accounting for some of the decline; almost all the rest were almost certainly moderates, not conservatives.)
It also seems unlikely that the moderates who stayed home did so because they felt Democrats had moved too far to the left. First, if that were the case, wouldn't you expect them to turn out and vote for Republicans to provide balance? Second, moderates by their very nature tend not to look at things in ideological terms. Undoubtedly this will be a matter of debate, but it seems most likely to me that moderates who stayed home did so because they feel alienated from the political system and do not believe that it is delivering for them. That's not an issue of being right or left -- it's an issue of not moving forward quickly enough.
In the end, it's very important to remember that the moderates who did vote still supported Democrats by double-digit margins and moderate voters are still far more likely to vote for Democrats than Republicans. Democrats may have to work harder to win the votes of some disaffected moderates, but Republicans aren't even close to winning them over.
In fact, as big a win as this election was for the GOP, it could ultimately be a handicap: with 66% of their coalition consisting of conservatives -- up from 55% in the last mid-term -- they are more beholden than ever to the right. And that's going to make it harder, not easier, for them to deliver the kind of progress that will win over moderate voters.