In a vote that reflected divisions among Cambridge residents, the city’s School Committee narrowly approved a contract extension for Superintendent Thomas D. Fowler-Finn, an administrator known equally for boosting test scores and a brusque management style that has alienated colleagues and parents alike.

The deciding vote was cast by newly-elected Cambridge Mayor E. Denise Simmons, who chairs the six-member committee.

This November, voters replaced one critic and one supporter of the superintendent with a different critic and a different supporter, thus keeping the overall balance at three opponents and three allies.

As a result, the vote fell to the city’s mayor. And Simmons, a former School Committee member who was chosen as mayor by the City Council earlier this month, held her cards close to her chest.

She ultimately cast a vote in Fowler-Finn’s favor, inflaming the divide between the pro- and anti-superintendent camps.

“I was disappointed in Mayor Simmons’ vote,” said Luc D. Schuster, a committee member who voted against the contract extension. “She had been a vocal opponent of the superintendent in years past as a city councilor.”

Nancy Tauber, a committee member who was elected on a pro-Fowler-Finn platform, praised the superintendent for his skill in leading the district while weathering attacks from his opponents.

“He’s been raked over the coals at School Committee meetings,” said Tauber. “But he continues to do his job in a professional manner.”

Over the years, the superintendent’s critics have called him “autocratic” and “uninspiring,” citing his top-down approach to leadership and inability to collaborate with principals and teachers.

But in his five years leading the district, test scores have risen—in some cases dramatically.

In 2006, Cambridge Rindge and Latin, the city’s only public high school, posted a 20-point increase in its English test scores and a 19-point increase in mathematics—results that have caused many in the community to rally behind Fowler-Finn.

But even his success in boosting scores has brought him some criticism: committee member Marc C. McGovern said yesterday that Fowler-Finn’s “test-oriented” approach stifles the creative freedom of teachers.

“I envision a school system where we show progress on tests, but are not ruled by them,” said McGovern, who publicly opposed the superintendent in 2006 and voted against the extension this time around.

McGovern added that despite the improvements in overall scores, not enough progress has been made on closing the achievement gap between white and minority students.

Negotiations about the length of the contract extension—which is not yet known but could run up to three years past its current expiration in August 2008—will likely begin in early February.

Tauber said that the committee would be wise to finish the negotiations quickly so as not to be distracted from what she called its main focus.

“I think all of us know we need to move on this quickly, and get onto the business of educating our children,” she said.

This is not the first time that Fowler-Finn has split the committee.

In August 2006, the committee approved Fowler-Finn’s current contract—his second one since he arrived in Camrbdige in 2003—by a four-to-three vote.

—Staff writer Cora K. Currier can be reached at ccurrier@fas.harvard.edu.

—Staff writer Vidya B. Viswanathan can be reached at viswanat@fas.harvard.edu.