Democratic U.S. Senate candidate Sara Gideon gets a tour of ReVision Energy in South Portland in August 2020. Credit: Troy R. Bennett / BDN

A new poll released Wednesday showed House Speaker Sara Gideon with a 12-point lead over U.S. Sen. Susan Collins and a bigger Maine lead for presidential candidate Joe Biden in a significant outlier favoring Democrats far more than any other poll this year.

In the toss-up Senate race, the Quinnipiac University poll moved in the opposite direction of an AARP survey last week that found the race tightening, with Gideon leading Collins by just one point among likely voters. In Quinnipiac’s last Maine poll, released in early August and focused on registered rather than likely voters, Gideon led Collins by four points. The Democratic House Speaker has led in every public poll this year, but only by narrow margins.

This new poll included 1,183 likely voters and was conducted between Sept. 10 and 14. The margin of error was 3.7 percent and the sample was weighted to match key demographics. Mary Snow, a polling analyst at Quinnipiac University, noted that the poll was conducted for several days after the first Senate debate on Friday, which may have moved some voters.

But compared to other polls, the survey showed significant differences for Gideon among men and non-college educated voters, with whom she has previously trailed. The poll found her up slightly among both groups of voters, though the result was within the margin of error.

Collins, a fourth-term Republican, led among voters who cited the economy or law and order as their top issue, the poll found. Gideon led among voters who cited health care, climate change, coronavirus or the Supreme Court as their top issue.

The survey did not ask about support for independent candidates Lisa Savage and Max Linn, though 1 percent said they would vote for someone else and 3 percent did not know who they planned to vote for. Polling from AARP and the Bangor Daily News has shown that Savage supporters are more likely to name Gideon as a second choice in a ranked choice runoff.

The poll found Biden over President Donald Trump statewide, 59 percent to 38 percent. It also showed Biden winning in the 2nd District with 53 percent to Trump’s 44 percent. That was perhaps the most surprising result of the poll since Trump won the district and its single electoral vote by 10 points in 2016. Polling this year has shown it virtually tied.

Both the Senate and presidential results from Quinnipiac are significantly better for Democrats than other polling in the last few months, even as previous polling has shown Democrats with an advantage most of the year.

Quinnipiac is rated a B+ pollster according to FiveThirtyEight, with a track record of calling 83 percent of races correctly and a bias of 0.2 percentage points in favor of Democrats. Its methodology, including weighting on demographics, is fairly similar to that of other pollsters who have found narrower results in Maine in recent months.

Statisticians generally say that reading too much into any poll is a mistake, but outliers should be incorporated into polling averages.

“In a race with many polls, any one poll should rarely make all that much news. But you shouldn’t ‘throw out’ the poll either,” wrote Nate Silver, editor in chief of FiveThirtyEight, in a blog post last year.

With seven weeks to go, polls also are not predictive. They show where voters stand at the current moment. Even with record numbers of Mainers requesting absentee ballots during the coronavirus pandemic, voters will not get their ballots until early October.

“A lot can happen between now and Nov. 3, so that is something to keep in mind,” Snow said. “This is a snapshot.”

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