If the Supreme Court rules in favor of same-sex marriage, TV can take at least some of the credit.
The court is scheduled to begin hearing arguments Tuesday on the first of two cases about whether gay and lesbian couples should be able to marry. It's been one of the hottest political issues in Hollywood since stars rallied against Proposition 8, the law the justices will consider first.
But the entertainment industry's most successful campaign may be the one playing out in American living rooms.
Also read: 'Modern Family' Co-Creator Steve Levitan: I'd Be 'Happy' If Show Helped Overturn Prop 8 (Exclusive)
From "Will & Grace" 15 years ago to "Modern Family" today, television shows have brought homosexual characters into the homes of people who might otherwise have thought they didn't know any gays.
"Nothing undoes someone's homophobia more effectively than knowing someone who's gay," said It Gets Better co-founder Dan Savage in an interview last year with TheWrap.
For years, Savage said, he was the only gay person some heterosexuals knew -- or at least felt they knew -- thanks to his column in alt-weeklies.
Also read: Dan Savage Takes 'It Gets Better' to MTV -- and May Have a Deal for Santorum
But now heterosexuals have more gay friends then ever -- at least on their TV screens.
They include Will and Jack from "Will & Grace," living on in reruns. And David and Keith (right) on HBO's "Six Feet Under," parents of two boys. And the many women of "The L Word."
ABC introduced us to Cam and Mitchell, the gay parents of an adopted daughter on "Modern Family," one of the most popular shows on TV. This season brought us gay parents on "The New Normal." And Savage has gone from writing an advice column to doling out advice on MTV.
Are we leaving anyone out? Of course we are -- decades' worth of characters. As well as recent ones on "Game of Thrones,""True Blood" and "Glee." And that's to say nothing of the sympathetic gay characters in films like "Milk,""A Single Man" and "Brokeback Mountain."
But television is more intimate than movies -- and offers more nuanced and realistic portrayals of gay couples than ever before. We invite television characters into our rec rooms and bedrooms, and watch them grow and evolve week after week for years. While movie characters leave us after a couple of hours, those on TV arrive at a set time every week, in visits that can add up to days.
"If we played even the tiniest role in helping to defeat Prop 8 and giving all gay people the equal rights they deserve, then I'm a happy man," said "Modern Family" co-creator Steve Levitan.
But if creators aren't willing to take the credit, others are willing to give it -- including Vice President Joe Biden.
He said on "Meet the Press" last May that "Will & Grace" has done "more to educate the American public than almost anything anybody has done so far."
In the same interview, Biden said that he agreed with same-sex marriage -- and a slew of politicians followed suit. Among them was Biden's boss, President Obama as well as former secretary of state Hillary Clinton, who both in 2008 only supported civil unions.
Biden's change of heart led to Obama announcing one as well -- and in November, he became the first person to win the executive office while supporting same-sex marriage.
It was a far cry from the 2004 campaign, when Republicans tried to get anti-gay marriage initiatives on state ballots to drive conservative turnout and help then-President Bush.
This is a different country than it was then. Last week, a Washington Post-ABC News poll found that 58 percent of Americans believe gay and lesbian couples should be able to wed, up from 37 percent in 2003.
If the increasing number of loving gay couples on television hasn't helped that evolution, it certainly hasn't hurt. Once, homosexuals on television were shameful perverts, if not criminals. Then they were comic relief. Then sidekicks.
In the last decade, they have become as fully formed as any of the other characters on our two-dimensional screens.
So it will be interesting to see, when the justices rule later this year, if they've been watching the same show as everyone else.
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