By Jon Keller

BOSTON (AP) — A new poll shows Democrat Edward Markey has opened up a double-digit lead over Republican Gabriel Gomez in Massachusetts’ special U.S. Senate election.

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The UMass Lowell-Boston Herald poll found 56 percent of those responding favored Markey compared with 36 percent supporting Gomez. Seven percent were undecided.

Of those polled who said they plan to vote for Markey, 76 percent said this was a firm choice compared with 67 percent of voters who said they will vote for Gomez.

The poll also found Markey leading Gomez in all gender, age, education, income and ethnic categories.

Markey’s favorability rating stands at 48 percentage compared to 34 percent for Gomez.

The telephone poll of 600 Massachusetts voters from June 15-19 has a margin of error of plus or minus 4 percentage points.

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The election to fill the seat left vacant by the resignation of John Kerry is Tuesday, June 25.

Other findings from the poll include:

— Thirty-four percent of registered voters polled said the economy is the most important issue in politics, followed by jobs at 27 percent, immigration at 12 percent, gun laws at 10 percent and environmental issues at 7 percent;

— Sixty-five percent of registered voters polled said they favor a federal ban on assault weapons, while 27 percent were opposed;

— President Obama remains popular in Massachusetts, with 61 percent of registered voters saying they strongly or somewhat approve of how the president is handling his job.

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Copyright 2013 The Associated Press.

Jon Keller