In Middlesex's 31st District, Democrat Jason Lewis said Tuesday night that sticking with a positive campaign helped him win.

With 100 precincts reporting, Lewis  defeated Republican Brian O'Connor and Independent Chad Riley, 52 percent to 24 percent to 24 percent, respectively.

"I think it was that we won a strong campaign," Lewis told PolitickerMA.com. "A couple hundred volunteers who joined me over the last year, and we did a lot of work, going to door to door and talking to thousands of people."

The race in Middlesex's 31st District has been marked by negativity as Riley has charged that Lewis is a socialist because he was endorsed by Mass Alliance, a progressive group.

Lewis said his campaign responded to the charges by sticking to its positive message.

"I feel proud of our campaign," he said. "We stayed positive, we stayed focused on the issues and concerns of the people of the district."