Harvard professor Elizabeth Warren has pulled almost neck-and-neck with Sen. Scott Brown (R-Mass.), according to a new poll released today.

In a horse-race matchup, she garnered 38 percent while Brown pulled in 41 percent of 1,005 registered Massachusetts voters. Twenty-one percent volunteered that they didn’t know or would vote for someone else.

Although Warren faces a crowded Democratic primary field, she is seen as the frontrunner, an image this poll confirms. Thirty-six percent of potential Democratic primary voters said they would like to see her face off with Brown. No other candidate garnered more than 5 percent.

Warren has substantial support among the Democratic political establishment in Boston and Washington, D.C. Rep. Niki Tsongas (D-Mass.) will endorse Warren this afternoon.

The UMass-Lowell/Boston Herald poll also found that 50 percent of registered voters believe Brown has been “an independent voice” for the Bay State, playing into a key narrative the Brown campaign hopes to emphasize.

The poll also found that Warren still has a lot of room to make an impression with Massachusetts voters. Fifty-two percent of those polled had a favorable opinion of Brown, while 30 percent had a favorable view of Warren. But 37 percent had never heard of Warren and 14 percent of those who had were still undecided. Only 29 percent of registered voters had an unfavorable opinion of Brown, and only 18 percent had an unfavorable view of Warren.

The live telephone interview poll, conducted Sept. 22 to Sept. 28 had a margin of error of 3.8 points.

Roll Call Politics rates the Massachusetts Senate race a Tossup.