(CNN) – The Change To Win coalition – seven unions that represent between five and six million members nationwide – became the latest labor group to endorse Barack Obama Thursday.

"We think it's time to bring this nomination to a close," said the group's chair, SEIU official Anna Burger. The group's leadership decided to endorse Obama during a Thursday morning conference call.

Change to Win, which broke away from the AFL-CIO after the last election cycle, is led by the heads of its seven member unions and three other labor leaders, including Burger.

A majority of the group’s member unions have already backed Obama: the Teamsters – which revealed their support for Obama Wednesday – UNITE Here, the Service Employees International Union and the United Food and Commercial Workers Union. The decision does not need to be unanimous.

The three other unions, which have not endorsed Obama, are the United Brotherhood of Carpenters, Laborers International Union, and United Farm Workers. United Farm Workers endorsed Hillary Clinton earlier this year.

Change to Win spokesman Greg Denier said there had been no negative votes on the endorsement, but that the three unions that had not yet backed Obama had abstained from the day’s vote. (He said the two unions that had not yet endorsed any candidate did not weigh in because they needed to complete an “internal process” before making any announcement on the presidential race.)

The New York senator has also received nods from several other unions, including the American Federation of State County and Municipal Employees.

(updated Thursday afternoon to reflect official announcement)

–CNN’s Mark Preston and Rebecca Sinderbrand