(CNN) - Democrat Martha Coakley leads Republican Scott Brown by 15 points in the battle to fill the final three years of the term of the late Sen. Ted Kennedy of Massachusetts, according to a new poll.
The Boston Globe survey, conducted by the University of New Hampshire, was released Sunday, nine days before Bay State voters cast ballots in the special election.
According to the poll, half of the percent of people likely to vote in the contest say they're backing Coakley, the state's attorney general, with 35 percent supporting Brown, a state senator. Nine percent questioned are undecided and 5 percent support Independent Joseph Kennedy, a third party candidate who is not related to the late senator.
The poll indicates that Coakley's lead over Brown grows to 17 points, 53 percent to 36 percent, when undecided voters leaning toward a candidate are included in the tally. And nearly two-thirds of Brown supporters believe that Coakley will win. Brown is hoping to become the first Massachusetts Republican since 1972 to win a U.S. Senate seat.
"She's simply better known and better liked than Brown," Andrew E. Smith, director of the University of New Hampshire Survey Center, told the Globe.
The Coakley campaign announced Sunday that former President Bill Clinton and five-term Sen. John Kerry of Massachusetts will team up at a rally for Coakley on Friday in Boston. Brown spent part of Sunday greeting fans of the NFL's New England Patriots, before the team's playoff game.
The 77-year-old Kennedy, who died of brain cancer in August, was the fourth-longest serving senator in American history. Paul Kirk, a long time adviser and friend to Kennedy, is serving as his interim replacement.
The Boston Globe/University of New Hampshire poll was conducted January 2-6, with 554 likely special election voters questioned by telephone. The survey's overall sampling error is plus or minus 4.2 percentage points.
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