Though the 2010 census is unlikely to reflect major changes in the socioeconomic and ethnic makeup of Cambridge over the past ten years, community leaders say they hope that “hidden” groups—specifically same-sex couples and the Portuguese-speaking population—will be more accurately represented in this year’s count.

For the first time, same-sex couples in Cambridge will be officially recognized on the census forms. In the past, the form only allowed heterosexual couples to describe themselves as “married,” but the Census Bureau announced last year that in 2010 the survey will recognize same-sex couples who report being married.

John W. Gintell, co-chair of the Cambridge LGBT Commission, said he hopes that comprehensive statistics will help open minds about the presence of same-sex couples in the Cambridge community.

“Knowing about how many same-sex couples are out there, living their lives, will help remove some people’s prejudice,” Gintell said.

Meanwhile, leaders in the Portuguese-speaking community are encouraging members to write “Portuguese” as their ethnicity on census forms, instead of White, Black, or Latino. Leaders hope that the write-in campaign will result in a census that represents a more accurate count of a population that, while large, has been invisible in federal statistics.

“The Portuguese community is severely undercounted,” said Paulo R. Pinto, executive director of the Massachusetts Alliance of Portuguese Speakers. “It is the second most spoken language in Massachusetts. We need to be counted to empower this community.”

Members of the Portuguese-speaking community—which includes those from Brazil and Cape Verde—number close to 15,000 in Cambridge, and as much as 1 million by conservative estimates in Massachusetts, according to Pinto.

The Massachusetts Alliance of Portuguese Speakers, the LGBT Commission, and other community groups are working with the Cambridge Complete Count Committee—formed by then-Cambridge Mayor E. Denise Simmons last year—to promote broader participation in the census.

Census data is used to allocate federal funds, which sometimes target specific populations. In the case of Portuguese-speaking Cantabrigians, such funds would go toward social services and educational programs in Portuguese.

In addition to reflecting the presence of these newly-represented communities, the 2010 census will likely show population growth, as over 4,000 housing units were added to the city in the past ten years, according to Clifford M. Cook, planning information manager for the city.

Cook said that new dormitories at Harvard and MIT will likely translate into an increase in the student population, though he also anticipated that the city’s population will be on average older than in past years, as baby boomers age. Cambridge school enrollments have stayed relatively constant, Cook said.

But the socioeconomic and ethnic makeup of Cambridge is unlikely to have changed significantly. The high rents and cost of living mean that those who can afford to live in Cambridge are either in high-income brackets or qualify for low-income housing—and those populations stay relatively constant, according to Michael J. Johnston, deputy executive director of the Cambridge Housing Authority.

The last census saw a shift in socioeconomic diversity as rent-control ended in Cambridge, but the effects of that are “water well under the bridge” now, Cook said.

He added that he does not expect to see income statistics change as a result of the recent economic recession, citing Cambridge’s highly educated population as an insulating factor.

“It hasn’t made much of a dent overall,” Cook said of the financial crisis. “If you’re gonna pick a place to be in a depression, Cambridge isn’t bad.”

Because Cambridge remains a relatively wealthy city with limited low-income housing, it has not experienced the same influx of immigrants as Greater Boston has in the past decade.

Cambridge also bucks the trend seen in Boston and nationwide of a large increase in Hispanic populations. The ethnic makeup of waitlists for public housing in Cambridge has changed little over the past ten years, with Portuguese speakers and Haitians comprising most of the minority applicants, according to Johnston.

Much of the Portuguese-speaking community in Cambridge remains in the city because members purchased homes years ago when property values were lower, and homeowners now rent to newer immigrants well below the market rate, according to Pinto.

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