[cnn-photo-caption image= http://i2.cdn.turner.com/cnn/2009/images/04/16/art.schmidtpt0416.gi.jpg caption="At a gathering of a gay Republican group, Steve Schmidt will make the case Friday that the Republican Party should support same-sex marriage."]
WASHINGTON (CNN) – Steve Schmidt, a key architect of John McCain's presidential campaign, is making his first public return to Washington a bold one.
Schmidt will use a speech Friday to Log Cabin Republicans, a gay rights group, to urge conservative Republicans to drop their opposition to same-sex marriage, CNN has learned.
"There is a sound conservative argument to be made for same-sex marriage," Schmidt will say, according to speech excerpts obtained by CNN. "I believe conservatives, more than liberals, insist that rights come with responsibilities. No other exercise of one's liberty comes with greater responsibilities than marriage."
Schmidt makes both policy and political arguments for a Republican embrace of same-sex marriage.
On the policy front, Schmidt likens the fight for gay rights to civil rights and women's rights, and he admonishes conservatives who argue for the protection of the unborn as a God-given right, but against protections for same-sex couples.
"It cannot be argued that marriage between people of the same sex is un American or threatens the rights of others," he says in the speech. "On the contrary, it seems to me that denying two consenting adults of the same sex the right to form a lawful union that is protected and respected by the state denies them two of the most basic natural rights affirmed in the preamble of our Declaration of Independence - liberty, and the pursuit of happiness.
"That, I believe, gives the argument of same sex marriage proponents its moral force," Schmidt will say.
Politically, he will say that becoming more open and accepting is critical to reversing an alarming trend for Republicans - a shrinking coalition. He will note that Republicans should be especially concerned that McCain got crushed by Barack Obama among voters under 30, who are generally more accepting of gay couples and at odds with the GOP.
"Some Republicans believe the period of self-examination within the party necessitated by the loss of our majority status is mostly a question of whether the party should become more moderate or conservative. I think that's a false choice. We need to grow our coalition, but as I said, that's hard to do if we lose some votes while gaining others," says Schmidt.
Schmidt had previously expressed his personal support for gay marriage. Last month, he told the Washington Blade newspaper that he is in favor of legalizing it and that he voted against California's Proposition 8, which overturned a court ruling that had legalized the unions in that state.
In making the case, Schmidt is putting himself at odds with the position of John McCain, whose 2008 campaign he effectively ran.
McCain rarely talked about same-sex marriage or other social issues, but when he did, he made clear he was in line with social conservatives in opposing same-sex marriage.
"Have no doubt about my commitment to the unique status and sanctity of marriage between man and woman," McCain said on the campaign trail.
McCain's daughter Meghan has become a vocal advocate in recent months for gay marriage, and is slated to participate in the Log Cabin Republican convention this weekend.
In his speech Friday, Schmidt will acknowledge that his is a "minority view" in the GOP, but will also say, "I'm confident American public opinion will continue to move on the question toward majority support, and sooner or later the Republican Party will catch up to it."