Warren in Dot, Brown in Mattapan on small business stump

US Senator Scott Brown visited Auto Service and Tire in Mattapan Square on Monday morning.

Holding slim leads in a pair of new polls and coming off a campaign rally Saturday with Gov. Deval Patrick, U.S. Senate candidate Elizabeth Warren planned to tout support from small businesses Monday morning at an event Cedar Groves Gardens in Dorchester.

Warren was at the Adams Street business to promote “hundreds” of small businesses supporting her campaign to unseat Brown, who says Warren would support a raft of job-crushing taxes. Brown’s lone campaign event Monday was a 9:30 a.m. “Thank You for Building This” stop at Auto Service and Tire, 1590 Blue Hill Avenue in Mattapan.

A Western New England University Polling Institute survey of 444 likely voters, conducted Sept. 6-13, showed Warren with a 50-44 lead over Sen. Scott Brown. Pollsters said Warren “is relying on sizable support from Democrats and women to overcome Brown’s lead among independent voters and men.”

In the poll, Warren led Brown by 12 points, 53-41, among a larger sample of 545 registered voters.

The margin of error in the likely voter sample was plus or minus 4.6 percentage points, and the margin of error for the sample of all registered voters was plus or minus 4.2 percentage points.

Warren held a two-point lead over Brown, within the 3.3 percent margin of error, in Public Policy Polling survey results released Sunday that showed the race in a dead heat, as other polls have indicated earlier in the campaign. Warren trailed Brown 49-44 in the organization’s last poll and pollsters said she has gained ground by solidifying her support among Democrats. The survey found 53 percent of voters want Democrats to retain control in the Senate while 36 percent want Republicans to hold sway there.

The Public Policy Polling survey showed Brown leading among independents, the largest bloc of voters in Massachusetts, by a 56-35 spread. And while Warren logged a 51/43 favorable/unfavorable spread, Brown registered a 55-34 approval/disapproval split.

“Brown continues to be one of the more popular Senators in the country and he’s doing what he needs to do in this campaign, but his party label may end up being more than he can overcome,” PPP officials wrote, adding Warren was benefitting from a “monumental” gender gap, leading 56-36 among women.

Brown’s campaign over the weekend released a video featuring an endorsement from Sen. John McCain.

In August, McCain, who serves with Brown on the Senate Armed Services Committee, presided over a ceremony in which Brown was promoted to the rank of colonel in the National Guard.

“Just this last week, we saw violence erupt around the world, including Northern Africa and the Middle East. Our embassies came under attack and American lives were tragically lost, including our ambassador to Libya,” McCain said in a Brown endorsement video. “Scott understands the challenges we face, and he has the experience, wisdom and the temperament to influence the choices our nation makes.

State House News Service has posted these videos from Warren's appearance this morning: