In a tiny room in the back of The Piano Factory on Tremont Street about 25 people pulled old campaign signs off wooden frames and stapled fresh white poster board in its place. Children sat on the floor patiently painting the word “CHANGE” below letters written by their elders.

Roxbury for Obama volunteers, local politicians and their constituents spent last night preparing a “Get Out the Vote” campaign push before the Massachusetts primary on Tuesday.

“This is a race where the most in-tune field plan is going to get the vote,” said Rose Arruda, neighborhood coordinator for Sen. Barack Obama’s campaign.

In the two weeks Roxbury for Obama has been together, the group has organized phone banks and sign displays. Get Out the Vote — the effort to get as many Obama supporters as possible to the polls — is the group’s main event.

Transportation coordinators are working to get people who cannot transport themselves to the polls next week.

“We have some intense, driven volunteers who are getting the job done,” Arruda said.

Members said they plan to stand outside subway stations, passing out flyers during rush hour. Others will be calling and knocking on doors to remind people their votes matter.

Eve Lyman, organizer of the poster-making party, said turnout for events like the poster-making party shows the magnitude of grassroots’ support for Obama.

“I really think there is a struggle going on for the soul of this country,” Lyman said. “I think it has to do with whether we want to go on with the politics of greed . . . and self-interest . . . or whether we want to empower the people.”

With the support of politicians like Gov. Deval Patrick and Rep. Gloria Fox (D-Boston), the Obama movement in Boston has taken off. Fox, who attended the event, said she backs the Illinois senator because she believes his campaign is most in tune with the needs of the diverse group she represents.

“This is my district, this is my home, this is my city — I am a Bostonian,” Fox said. “I made my decision based on the candidate that I trust, the candidate that most understands the issues that I care about and that I work on for my community.”

Tracie Taylor, a marketing representative from Dorchester, said she volunteers for the group because she believes that Obama can bring much needed change to America.

“I holistically, I whole-heartedly, I not only support him, I believe in what he can do for this country,” she said.