In the Sports Illustrated piece in which he explains his decision to come out, Collins talks about how he felt when Kennedy described marching in Boston's 2012 Gay Pride Parade.
"I'm seldom jealous of others, but hearing what Joe had done filled me with envy. I was proud of him for participating but angry that as a closeted gay man I couldn't even cheer my straight friend on as a spectator," he wrote. "If I'd been questioned, I would have concocted half truths. What a shame to have to lie at a celebration of pride. I want to do the right thing and not hide anymore. I want to march for tolerance, acceptance and understanding. I want to take a stand and say, 'Me, too.' "
President Bill Clinton was also quick to endorse Collins's announcement.
"I have known Jason Collins since he was Chelsea's classmate and friend at Stanford," Clinton said in a statement. "Jason's announcement today is an important moment for professional sports and in the history of the LGBT community. It is also the straightforward statement of a good man who wants no more than what so many of us seek: to be able to be who we are; to do our work; to build families and to contribute to our communities."
"For so many members of the LGBT community, these simple goals remain elusive," Clinton continued. "I hope that everyone, particularly Jason's colleagues in the NBA, the media and his many fans extend to him their support and the respect he has earned."
Collins, who finished this season with the Washington Wizards, has also played for the Boston Celtics, Minnesota Timberwolves, New Jersey Nets, Atlanta Hawks and Memphis Grizzlies
"I didn't set out to be the first openly gay athlete playing in a major American team sport," Collins wrote in Sports Illustrated. "But since I am, I'm happy to start the conversation."
Collins's announcement is sure to reverberate politically in the weeks to come. First Lady Michelle Obama tweeted late Monday afternoon, "So proud of you, Jason Collins! This is a huge step forward for our country. We’ve got your back! -mo"
And while White House spokesman Jay Carney said Monday afternoon he has not spoken to the president about it, he told reporters, "I can certainly tell you that here at the White House we view that as another example of the progress that has been made and the evolution that has been taking place in this country, and commend him for his courage, and support him in his -- in this effort and hope that his fans and his team support him going forward."
Human Rights Campaign President Chad Griffin released a statement saying the 34-year-old athlete "has forever changed the face of sports."
"No longer will prejudice and fear force gay athletes to remain silent about a fundamental part of their lives," Griffin said. "By coming out and living openly while still an active NBA player, Collins has courageously shown the world that one's sexual orientation is no longer an impediment to achieving one's goals, even at the highest levels of professional sports."
This post has been updated.