Among the imagery included in a new MSBNC ad is a gay couple exchanging vows.

The ad is part of the network's new Lean Forward campaign.

The 60-second spot begins with a YouTube clip of young people enjoying a day at the lake, a marching band, a child sledding in the snow, the space shuttle hurling into space and a woman playing Wii.

After a male announcer says, “We hold these truths to be self-evident. That all men and women have certain unalienable rights,” an opposite-sex couple is seen kissing at their wedding, followed by two men in dark suits exchanging vows.

“Life, liberty and the pursuit of happiness,” the announcer adds. “And the freedom to believe that while history has gotten us this far, our best days are still ahead.”

“We are the United States of come as you are. Our differences are what unite us.”

Several MSNBC personalities are vocal advocates for gay rights. The cabler is also home to openly lesbian Rachel Maddow, who stars five days a week on The Rachel Maddow Show.