Today, Hollywood celebrities, Silicon Valley entrepreneurs, NFL stars, business, clergy and civil rights leaders launched Freedom to Marry’s “Say I Do” campaign urging President Obama to support the freedom to marry for gay and lesbian couples.

“My wife and I were married in May of 2010, and I can say without a doubt that marriage matters,” said Emmy Award winning actor Jane Lynch. “As President Obama continues his journey toward recognizing our right to equal taxation, protection and dignity under the law, I encourage him to listen to gay and lesbian couples and families so he can better understand how marriage equality affects us all.”

Freedom to Marry’s “Say I Do” campaign kicks off with a letter to the president signed by a diverse set of VIPs and open to Americans from every walk of life to sign. The letter calls for “clarity from the President” and urges him to “join us and the majority of Americans who support the freedom to marry.”

To read the full text of the letter, please click here. The letter will be delivered to the White House by same-sex couples and families later this spring.

“Freedom to Marry is proud that such a diverse and talented group of people is joining us to ask the President to ‘Say I Do’ to loving, committed gay and lesbian couples who want to marry,” said Marc Solomon, National Campaign Director for Freedom to Marry. “We appreciate the President’s journey towards supporting the freedom to marry and the concrete steps he’s taken along the way. Now we call on him to complete that journey on the side of fairness for gay and lesbian Americans and their families.”

Signers to the letter include actors Anne Hathaway, Jane Lynch, Eric McCormack, Martin Sheen, and Lily Tomlin; television host Ellen DeGeneres and actor Portia DeGeneres; musicians Melissa Etheridge, Mya, and Rufus Wainwright; high-tech entrepreneurs Jack Dorsey (creator of Twitter), Chris Hughes (co-founder of Facebook), Sean Parker (co-founder of Napster), and Mark Pincus (co-founder of Zynga); media/entertainment execs David Geffen (co-founder of Dreamworks SKG) and Bob Wright (former chairman and CEO of NBC Universal); NFL players Brendon Ayanbadejo and Scott Fujita; playwright Tony Kushner; civil rights icons Julian Bond, Chairman Emeritus, NAACP, and Helen Fabela Chavez (widow of Cesar Chavez and founder of Cesar E. Chavez Foundation); and Rev. Peter Morales (president, Unitarian Universalist Association). For a full list of original signers, click here.

In addition to the letter, the Say I Do campaign will focus on sharing poignant stories of same-sex couples and their family members with the President.