Massachusetts Congressman Barney Frank on Monday confirmed that a Democratic Party platform draft included a gay marriage plank.

Frank, a member of the platform drafting committee, said the addition was unanimously approved by the committee. The committee will finalize the platform at a meeting next month in Detroit. Democrats meeting in Charlotte on September 3 will vote on the platform.

In March, Freedom to Marry launched its Democrats: Say I Do campaign to promote a marriage equality plank in the platform. More than 42,000 Democrats have joined the campaign, including Democratic National Convention chair Antonio Villaraigosa, House Minority Leader Nancy Pelosi, U.S. Senate candidate Elizabeth Warren and nearly two dozen U.S. senators.

Marc Solomon, national campaign director of Freedom to Marry, who testified in front of the drafting committee in support of such language, applauded the move in a statement.

“We are grateful for the Platform Drafting Committee’s unanimous vote to include the freedom to marry in its draft of the Democratic Party platform,” Solomon said. “As I testified to the Committee on Friday, the Democratic Party has a noble history of fighting for the human and civil rights of all Americans. We are proud that the Committee is including language that will ensure the Party is leading the way forward in supporting marriage for loving and committed same-sex couples and their families.”