Whenever the president of the United States comes to Seattle, there's always a swarm of looky-loos standing around, trying to get a glimpse, to say they were in the immediate proximity of a man who has made history. Our presidential audiences have often been angry, occasionally been giddy, and frequently been packed full of people obsessed with some vague plan to forward their own personal agenda. But President Obama's speech at the Paramount last Thursday drew a very different crowd: It was a battalion of happy people out to demonstrate their gratitude.

People carrying signs and banners thanked President Obama for his announcement the day before that he "think[s] same-sex couples should be able to get married." There was something more to the waves of adulation than simple gratitude for his supportive statements, though. As Washington State prepares for Referendum 74, a gay-marriage vote that will likely appear on the fall ballot, many revelers believed President Obama may have handed the pro-marriage-equality, approve-R-74 forces the leverage they need to win.

Josh Friedes, the marriage equality director for Equal Rights Washington, calls President Obama's statement "a game-changer," because it has generated or will generate "hundreds of thousands of conversations in Washington." He explains that because of the president's announcement, gay marriage dominated the news cycle for 72 hours last week and is still a major topic in the national conversation. What this means, he says, is that "at the water cooler, and at Starbucks, and at barbecues, and at churches, people are going to be talking about marriage equality." When the public talks about marriage equality, Friedes says, marriage equality wins.

The numbers back him up.

Alison Peters cites a poll of 600 Washington voters that her firm, Alison Peters Consulting, performed in June 2011. It was a watershed moment for marriage equality in Washington because it was the first poll in which a majority of voters supported gay marriage—55 percent of likely voters approved marriage equality—but a discovery that Peters made over the course of the poll was even more meaningful.

It comes down to this: Talking about gay marriage greatly increases your chances of supporting marriage equality. Only 34 percent of voters who've never had a conversation about gay marriage support it. But 56 percent of all voters who have talked about gay marriage with a straight person support marriage equality. And even more impressive: 69 percent of all voters who have had a conversation about marriage equality with a gay person support marriage equality. All together, two-thirds of voters who have had a conversation about marriage equality support it. They've been forced to think through their position. That "swing of 35 points" (from 34 to 69 percent) between people who have and haven't had a conversation, Peters says, "is staggering from a statistical standpoint."

"People who were kind of squishy, what we call the mushy middle" on gay marriage, Peters explains, "become more supportive over time, the more they talk about it. It's kind of a wave." In fact, support of gay marriage over the course of the poll increased from 52 percent at the beginning of the call to 55 percent at the end; the poll itself served as a conversation during which people seriously considered the consequences of their actions and the true meaning of their beliefs.

Part of the reason we saw support for marriage equality pass the 50 percent mark last year is because the issue has been discussed so much in recent years. In 2009, voters narrowly approved a measure that extends domestic partnership rights to same-sex couples. That social pressure—from headlines and conversations about the vote—may be the reason for a bump in support. Of the people who had only recently come around, 22 percent of voters acknowledge that their position has changed within the last five years.

So having a conversation is the best tool available for marriage-equality supporters. President Obama's announcement, many believe, helps provide that crucial uptick again in Washington State just as a key vote approaches.

But Friedes says that the way President Obama supported gay marriage was important, too, because he provided a perfect model for people who are on the fence: "He talked about how he was influenced by friends and family members" and "he also talked about his being Christian," Friedes says, and that helps with the realization that "there's nothing contradictory about being Christian and being a supporter of marriage equality." In talking about his journey to embracing gay marriage, Friedes says, President Obama "gave people permission to talk about their journey," from their opposition to marriage equality to their support. In effect, he said that it was okay to change your mind and reinvestigate an issue you once were on the wrong side of.

"People need to understand that they hold the power in the conversations they have," Friedes says. What moved the president were "his interactions with people he already knew," and by talking about that, he provided a road map for Washington to become the first state to approve marriage equality via popular vote.