Poll: Sen. Brown, Warren Race A Statistical Tie

On the day Democrats in Massachusetts gather to endorse Elizabeth Warren for the U.S. Senate, a new poll shows the contest between the Harvard Law School professor and Republican incumbent Sen. Scott Brown is statistically tied.

The poll has Brown leading Warren 39 percent to 37 percent. Conducted by the University of New Hampshire Survey Center for the Boston Globe, the poll has a margin of error of plus or minus 3.8 percentage points. The results are basically unchanged from a poll in March.

Several poll questions explored voter reaction to the controversy over Warren's claims to Native American heritage. Seventy-two percent of respondents said the issue would not affect their vote. However, 31 percent of voters who consider themselves independents said the issue makes them less likely to support Warren.

Andy Smith, the director of the survey center, said the independent vote is critical for Brown to build a coalition in a state so dominated by Democrats.

"Brown has to put together ... the small block of Republicans, plus a significant number of the independents," Smith said.

On Friday, Warren took part in a number of interviews with media outlets in an attempt to put the controversy to rest.