"Because of the 'gay exception' created by DOMA, America's legally married gay and lesbian couples — including servicemembers risking their lives on the front lines for our safety — are treated as strangers under federal law, rather than provided the respect and protections federal law normally assures to married couples and their loved ones," said Evan Wolfson, founder and president of Freedom to Marry. "This broad and diverse coalition has come forward to urge members of Congress to end the unfairness. In America, we don't have second-class citizens, and shouldn't have second-class marriages, either."

"The federal government should not be in the business of picking which marriages it likes and which it does not, but that is exactly what DOMA does," said Joe Solmonese, Human Rights Campaign president. "The breadth and depth of this coalition shines a bright light on the heart wrenching discrimination against loving, committed families caused by DOMA."

The Senate Judiciary Committee considered the bill with a hearing in July and subsequently passed the legislation out of committee in November.

DOMA denies legally married gay and lesbian couples any of the over 1,100 federal responsibilities and protections of marriage. These include Social Security survivor's benefits, federal employee health benefits for spouses, protections against spouses losing their homes in cases of severe medical emergencies, the right to sponsor a foreign-born spouse for immigration, the guarantee of family and medical leave and the ability to file joint tax returns, among many others. 51 percent of voters oppose DOMA while only 34 percent favor it, according to a March 2011 poll by HRC and Greenberg Quinlan Rosner Research.

A full list of the coalition members follows:

Alliance for Justice, American Civil Liberties Union, American Federation of Government Employees, American Federation of Musicians, American Federation of State, County & Municipal Employees, American Federation of Teachers, Americans for Democratic Action, Anti-Defamation League, Association of Flight Attendants, Center for American Progress, Coalition of Labor Union Women, COLAGE, Courage Campaign, Communications Workers of America, Family Equality Council, Feminist Majority, Freedom to Marry, GLAD, Gay & Lesbian Medical Association, Gay, Lesbian & Straight Education Network ( GLSEN ) , Human Rights Campaign, Immigration Equality, Interfaith Alliance, International Union, UAW, Lambda Legal, The Leadership Conference on Civil and Human Rights, Log Cabin Republicans, MALDEF, National Black Justice Coalition, National Center for Lesbian Rights, National Council of Jewish Women, National Education Association, National Fair Housing Alliance, National Gay and Lesbian Task Force, National Organization for Women, National Partnership for Women and Families, National Women's Law Center, People for the American Way, PFLAG, Pride at Work, AFL-CIO, Religious Action Center of Reform Judaism, Services and Advocacy for GLBT Elders ( SAGE ) , Service Employees International Union, Servicemembers Legal Defense Network, Stonewall Democrats, Third Way, Unitarian Universalist Association, United Electrical, Radio and Machine Workers of America ( UE ) , United Food and Commercial Workers International Union, and USAction.