The final Emerson College Polling survey of the Massachusetts Democratic Senate Primary finds incumbent Ed Markey leading Rep. Seth Moulton, 60% to 33%, while 7% are undecided. Since the May Emerson College poll, Moulton’s support increased one point from 32% to 33%, while Markey’s support grew by 23 points, from 37% to 60%. When the undecided voters are accounted for, Markey’s lead grows to 30 points, 65% to 35%.
“If these numbers hold, this race will mirror Markey’s successful ‘peak-late’ approach to winning in 2020, when the Senator moved from 16 points behind in our May poll to 12 points ahead in August, a 28-point swing, ultimately winning by 11,” Spencer Kimball, executive director of Emerson College Polling, said. “This cycle, the margin similarly shifted from a five-point lead in May to a 30-point lead in the final Emerson poll.”
The May Emerson College poll noted groups most favorable toward Markey, including women and young voters, were among the most undecided. Now, with days until primary day, women break for Markey by 28 points, 64% to 36%, and voters under 40 by 32 points, 66% to 34%. Moulton’s support is highest among voters over 70, at 38%, but still trails the Senator by 24 points among this group.
“While Moulton made Markey’s age a central issue in the campaign, younger voters appear more likely than older voters to support Markey, suggesting the campaign did not create the generational divide Moulton may have anticipated,” Kimball said.
Methodology
The Emerson College Polling Massachusetts Democratic Primary survey was conducted August 28-29, 2026. The sample of likely Democratic Primary voters/those who have already voted includes a sample size of n=550 with a credibility interval of +/- 4.1 percent.
It is important to remember that subsets based on demographics, such as gender, age, education, and race/ethnicity, carry with them higher credibility intervals, as the sample size is reduced. Survey results should be understood within the poll’s range of scores, and with a confidence interval of 95% a poll will fall outside the range of scores 1 in 20 times.
Data was collected by contacting a probability-based panel of voters provided by Consensus Strategies using MMS text-to-web, and panel interviews provided by PureSpectrum. All respondents were recruited using customized links that prevent responses from anyone outside of the poll’s sample frame. Panel responses were matched to the Aristotle voter file using respondents’ full name and ZIP code. The survey was hosted on QuestionPro. The data sets were weighted by gender, education, age, and region based on U.S. Census parameters and voter file data. The survey was offered in English.
All questions asked in this survey with exact wording and order, along with full results, demographics, and cross tabulations can be found below.
