After yesterday’s Public Policy Polling survey finding that the special election to fill Ted Kennedy’s Senate seat was a toss-up, a Boston Globe poll released today finds Democrat Martha Coakley beating Republican Scott Brown by a 15-point margin.
Polling a special election is difficult, of course, because it’s hard to predict the composition of the electorate. In the PPP survey, 44 percent of those polled were Democrats and 39 percent were independents, while the Globe had Democrats outnumbering independents by a nearly 4-to-1 margin, or 56 percent to 15 percent. But the fact that PPP detected more voter apathy among Democrats accounted for only part of the discrepancy.
Even if you put asside the weighting of the electorate, the polls have drastically different results. In the PPP poll, Brown crushed Coakley among independents, by a whopping 63 percent to 31 percent margin. By contrast, in the Globe poll, Coakley actually has a slight edge with independents, with 41 percent support compared to Brown’s 40 percent.
Some have noted that the Globe poll was taken from Jan. 2-6th, while PPP was in the field from Jan. 7th-9th, but the timing was so close that it couldn’t really explain the dramatic change. It’s also worth keeping in mind that PPP is the firm that gave conservative challenger Doug Hoffman a huge lead in New York’s 23rd Congressional race that was ultimately won by Democrat Bill Owens.
My personal take is that I simply cannot imagine Massachusetts voters electing a Republican to fill Ted Kennedy’s Senate seat so that he can become a vote against the health care bill. I think the PPP poll was enough to scare Democrats into doing what they need to in the week leading up to the Jan. 19 election to make sure their voters turn out. But it will be interesting to see how independents do vote, because that will be an indication of what we may expect in other states and districts that aren’t as deep blue as Massachusetts.
UPDATE: Giving it some more thought and looking at the numbers a bit more, it turns out the Globe only polled 81 independents, while PPP polled about 290. Such a difference in sample size could explain the wide difference in results among independents, and perhaps lend more credence to the PPP numbers among this group. If I were a betting man, my guess would be that indendents are probably more pro-Brown than the Globe poll suggests, but that the electorate will end up being more Democratic than what’s reflected in the PPP survey.