Reply #27: I find this very interesting....lack of enthusiasm vs enthusiasm for taking part in a robopoll

[Jennicut]

* Republicans are excited Brown might win and thus more likely to answer their phone and listen to political messages -possibly be invited to take a survey - when the phone is practically ringing off the hook with such calls. I suspect they'd be particularly enthused to participate in a poll and tell the world they're voting for Brown, to help build the sense he has unstoppable momentum. These folks certainly will vote but there's no upside in Brown's election-day numbers compared to the pre-election poll estimates.

* Democrats may be demoralized and scared after several weeks of Coakley campaign missteps and bad headlines. They may not be all that eager to pick up the phone for political calls. They also might be more skeptical of or angry about polls since they've been such downers for Coakley and President Obama lately, and thus, I would speculate, more likely to take a pass if invited to participate in one. None of that means these folks are less likely to vote, though - by now any sentient Democratic-leaning voter will know Coakley needs all their votes, and what's at stake. They might not be happy about how Coakley has run her campaign but they'll still be motivated to vote by a desire to deny a Republican the chance to do serious harm to Obama's agenda from Ted Kennedy's old seat. Obama is in Massachusetts today to remind them of exactly that (not that they're necessarily all that enthused about him at this point, either).

Of course, truly independent or "swing" voters are another vital factor, and if Brown wins enough of them he could overcome the inherent Democratic advantage in Massachusetts. But I'd think enthusiasm, or lack of it, would be more of an issue among stronger partisans.

In pollster speak, what this boils down to is "differential non-response," where one candidate's supporters are more likely than the other's to take a survey. It's suspected to be a big reason why exit polls in recent years have tended to overstate support for Democratic candidates. In the Massachusetts special Senate election I suspect it's inflating the Republican's poll numbers. Coakley has room to outperform the polls Tuesday even if her natural base is motivated by nothing more than fear of what would happen if her opponent pulls off an historic upset.
http://www.pollster.com/blogs/mokrzycki_are_ma_senate_polls.php