BOSTON -- Martina Robinson, the Green-Rainbow candidate for lieutenant governor, was trapped on the hydraulic lift of a city bus in Amherst.

"It happens a lot," Robinson said.

Robinson, a 30-year-old Belchertown resident, has cerebral palsy. She rides a 200-pound motorized wheelchair. When the lift jammed, there was no alternative but to wait for the Pioneer Valley Transit Authority to dispatch a repairman.

Twenty minutes later, Robinson was off the first bus, and aboard a second one headed to Hampshire College, where she would attend an event billed as a "political circus," but which serves as an opportunity for the candidate to campaign.

On the lawn at Hampshire, costumed Bread and Puppet Theater actors entertained an audience numbering in the hundreds. Political skits featured dancing telephones from the "National Security Agency Phone Tapping Ensemble," and a speech on liberty by Benjamin Franklin that ended with Franklin being hauled away by Homeland Security.

After the final skit, Robinson rolled her chair across the grass to greet friends and speak to voters.

Robinson's speech is impaired by her condition. Nevertheless, she was able to chat up a family camped out on the grass, asking them to take Green-Rainbow campaign literature out of her hand.

Robinson has some arm impairment, but she can use a computer. She feels her legs, but cannot walk. A state-funded personal assistant cooks for her, and helps her dress and bathe.

But her disability has not kept her down. She earned a B.A. in anthropology from the State University of New York at Purchase. She has also traveled to Japan and India as an advocate for the disabled.

Now she is running for lieutenant governor of Massachusetts.

Robinson became Green-Rainbow gubernatorial candidate and Grace Ross' running mate after Wendy Van Horne dropped out. Robinson had been Grace Ross's adviser on disability issues.

Van Horne was unable to devote enough time to the campaign given her full-time schedule as a nurse, according to Colby Peterson, media coordinator for the Ross campaign.

Robinson's life offers a perspective opposite that of many taxpayers and candidates. Her main source of income comes from Social Security benefits. As a result, there is not much interest in seeing her income tax returns.

"I don't make enough money to be eligible to pay taxes," Robinson said.

Robinson also has a ready answer for the delicate question of her ability to perform the duties of the lieutenant governor, such as presiding over the Governor's Council, which approves judicial nominations, and serving as acting governor when the governor is absent.

"Anyone running for office, in my opinion, needs a lot of help," Robinson said.

Robinson has never been elected to public office. She ran unsuccessfully for selectman in Belchertown. She has chaired meetings of political and disability groups. But is she ready to be governor?

"The people of Massachusetts could do a lot worse than me," Robinson said. "I'm very confident I could do it."

Former Lt. Gov. Evelyn Murphy knows the duties of the office. She also knows someone with cerebral palsy.

"The lieutenant governor serves as the extension for what the governor wants done," Murphy said. "Her (Robinson's) physical limitations make it harder for her to do, but don't disqualify her."

Robinson's optimism may stem from her upbringing. Robinson, an African-American, was raised in the Pentecostal tradition. Though no longer identifying with that form of Christianity, she remains a person of faith.

"God made me this way for a purpose," Robinson said. "I'm a very happy person."

Owen Broadhurst, an Agawam Green-Rainbow activist who is running for state representative, has served as an interpreter for Robinson. At a press conference introducing Robinson, she spoke to reporters; Broadhurst repeated her speech in case her remarks were not understood.

"She's a very warm, open, extraordinarily nice person. That's one of the things that struck me right away," Broadhurst said. "She's one of the most organized and committed activists I know."

Originally from Pennsylvania, Robinson said she moved to Massachusetts for "better services."

"In Pennsylvania they only wanted to give me three hours of care a day," Robinson said. "I couldn't move out of my parent's house, I couldn't go to grad school. I had to be permanently attached to my parents, which no one wants to do."

Now she is among those pushing for a change in Medicaid that would allow more disabled people to leave nursing homes and live independently.

Robinson calculates it costs $27,000 more to house a person in an institution rather than a community setting. She estimates 8,000 Massachusetts nursing home patients could be cared for in a community setting.

U.S. Rep. Marty Meehan, a Lowell Democrat, recently signed on as a sponsor of the bill.

Once a Democrat, Robinson joined the Green Party when she moved to Massachusetts.

"I kept waiting for the Democrats to do something and they never really did anything about the people I cared about," she said.

Though reluctant to criticize other candidates, Robinson is concerned about the corporate ties of Democratic gubernatorial nominee Deval Patrick.

"He's not as progressive as people think he is," Robinson said.

Robinson is an intrepid traveler. There was the time that she flew to Sapporo, Japan for the Sixth World Assembly of Disabled People. Unfortunately, her wheelchair was left on the tarmac at New Jersey. She demanded a loaner.

Robinson was one of only three disabled people to attend an international conference on women's health in New Delhi.

"Everyone was staring at you like you were the Creature from the Black Lagoon, until they realized you knew how to talk," Robinson said. "I'm sort of used to that."

Robinson is not the first candidate in a wheelchair to seek public office, but is among the most seriously disabled.

Former U.S. Sen. Max Cleland, D-Ga., lost three limbs in Vietnam. U.S. Rep. James Langevin, D-R.I., does not have the use of his legs, and only limited use of his hands. Like Robinson, he has a personal assistant to help him with daily tasks.

Both men worked their way up the political ladder before running for national office.

Robinson knows she may be unlikely to match their success at the ballot box. With her running mate, Grace Ross, currently polling at 1 percent, Robinson is realistic about her chances. If she doesn't win, she has a backup plan.

"I might go back and get my Ph. D," she said.

Rick Heller is a graduate student with the Boston Statehouse Program at the Boston University College of Communications.