Next week’s presidential debate could mark the first opportunity for President Obama and Republican presidential nominee Mitt Romney to face off on marriage in a race in which LGBT issues have figured less prominently than previous elections.

The debate — the first in a series of three for the presidential candidates — is set to take place on Wednesday at the University of Denver. The topic for the 90-minute debate is domestic policy, and LGBT issues and marriage equality would fall under that umbrella.

The moderator of the debate is Jim Lehrer, the executive editor and former news anchor for PBS NewsHour. It’s unclear if he’ll ask a question on LGBT rights or marriage at the debate. But a question on LGBT rights could create an opportunity for Obama, who endorsed same-sex marriage in May, to attack Romney for not only opposing marriage rights for gay couples, but supporting a U.S. constitutional amendment banning same-sex marriage.

Evan Wolfson, president of Freedom to Marry, said if a marriage question was posed to the candidates during the debate, he’d like to hear Obama “repeat the same heartfelt personal explanation” that he offered in May when he announced he completed his evolution in support of marriage equality.

“And I’d like him to point out that just as it was wrong to deny couples of different races — like his parents — the freedom to marry, so under our Constitution, it is wrong to exclude couples of the same sex from the commitment of marriage and the freedom to marry under the law,” Wolfson said.

Even though marriage will be on the ballot in four states and lawsuits are pending before the Supreme Court that would overturn the Defense of Marriage Act and California’s Proposition 8, both candidates have remained largely silent on marriage and other social issues and have focused more on the economy and national security.

Crosby Burns, a research associate on LGBT issues at the Center for American Progress, said the two candidates’ differing views on marriage could “not be more stark.”

“You have Mitt Romney who supports a Federal Marriage Amendment that would define marriage as the union between one man and one woman,” Burns said. “And Barack Obama, on the other hand, as you know has come out in May in favor of full marriage equality. If he’s asked a question at next week’s debate in Denver, I fully expect him to reiterate his unyielding support for marriage equality.”

But Dan Pinello, who’s gay and a political scientist at City University of New York, predicted that if the candidates are asked a marriage question during the debate, they would give “very abbreviated answers” because neither Obama nor Romney sees political gain by elevating the issue of marriage.

“If Jim Lehrer does say something about it, I think Mitt Romney will say this is an issue the states have to decide — nothing a president will have any authority over, but a state issue,” Pinello said. “I think Barack Obama, if he’s forced to address it, will say what he’s said before: it’s a personal issue … whatever he said a few months ago. But they’ll try to step around the issue as much as they can.”

Circumstances were much different in the recent past. Just two presidential elections ago, when Sen. John Kerry (D-Mass.) was running against then-President George W. Bush for the White House, the issue of marriage was a cornerstone of the Republican campaign at a time when 13 marriage amendments were on the ballot in states throughout the country.

In his 2004 State of the Union address, Bush said the country “must defend the sanctity of marriage” by passing a Federal Marriage Amendment to prevent “activist judges” from instituting same-sex marriage in their states. Asked about the issue on the campaign trail, Kerry would uncomfortably say he believes marriage is one man, one woman, but doesn’t think the U.S. Constitution should be involved.

Four years later, the issue of same-sex marriage figured less prominently in the contest between then-Democratic candidate Obama and Republican nominee John McCain. It came up during a forum hosted by Pastor Rick Warren of California’s Saddleback Church, when McCain said he thinks marriage should be left to the states, but would support a constitutional amendment banning same-sex marriage if his home state of Arizona were forced to recognize it. Obama also said he believed marriage is between one man, one woman because “God’s in the mix” — a position he has since changed — as he declined to support a Federal Marriage Amendment.

Warren isn’t even hosting the forum during this presidential election. In August, Warren announced he was pulling the plug on a similar event with Obama and Romney because of what Warren perceived as the uncivil discourse of both campaigns.

Pinello attributed the change in prominence of the issue of same-sex marriage to change in public opinion, saying eight years ago people were “very much” against marriage equality, but today a bare majority of the American public supports it.

“The Democrats don’t want to energize the social conservatives to go to the polls, and Romney doesn’t want to turn off moderates by appearing too harsh on social issues,” Pinello said.

Polls show a distinct change in position on same-sex marriage over the course of the last few election cycles. A report published in April by the Pew Research Center indicates a growing evolution in public opinion. In 2004, 60 percent of the American public opposed same-sex marriage while 31 percent supported it. Those figures changed in 2008 from 51 percent opposing it and 39 percent supporting it. This year, the report found the numbers had switched: 47 percent of people back marriage equality, while 43 percent oppose it.

In the past week, discussion of LGBT issues on the Republican side has come not from Romney, but his No. 2 on the ticket: Republican vice presidential candidate Paul Ryan. In an interview over the weekend with ABC affiliate WPTV in Florida, Ryan said when asked if he believes the military should return to the policy of “Don’t Ask, Don’t Tell” that the law shouldn’t be reinstated and “this issue is past us.”

“I talked to a lot of good friends of mine who are combat leaders in the theater, and they just didn’t think the timing of this was right to do this when our troops were in the middle of harm’s way in combat,” said Ryan. “Now that it’s done, we should not reverse it. I think that would be a step in the wrong direction because people have already disclosed themselves.”

On Tuesday, Ryan reiterated his opposition to marriage equality, saying “traditional marriage” is among the shared “universal human values,” even though same-sex marriage is legal in six states and D.C. and recognized in 11 countries. Ryan praised Romney at the Values Voter Summit earlier this month, as a “defender of marriage.”

The exception to the general lack of discussing LGBT issues came at the national conventions. At the Democratic National Convention, speakers weren’t shy about talking about their support for marriage equality. A video was played highlighting Obama’s support for it, and during his nomination acceptance speech Obama criticized “Washington politicians who want to decide who you can marry.”

Marriage references were more limited at the Republican convention, but the subject did come up, notably by former Arkansas Gov. Mike Huckabee, who criticized Obama for his support for “changing the definition of marriage” while still identifying as an evangelical Christian. In his nomination acceptance speech, Romney pledged to “honor the institution of marriage.”

Burns said the emphasis on the issue of marriage at the Democratic convention shows the party has grown to embrace it after being uncomfortable with the issue in years past.

“Every single speech that I heard almost in some way, shape or form — especially among the headliners — brought up gay and lesbian couples,” Burns said. “If you have the party leaders at the DNC convention touting their support for LGBT people, I think that’s indicative of the black and white differences between early elections and now where we have a party fully embracing LGBT equality rather than a lukewarm acceptance that you saw beforehand.”

One game changer for the election in terms of marriage could be the results of what happens with pending litigation before the Supreme Court challenging Prop 8. In the weeks remaining before Election Day, justices could decline to hear the case, allowing same-sex marriage to return to California immediately as soon as a mandate is issued from the U.S. Ninth Circuit Court of Appeals. Romney, who has supported Prop 8, may decide to incorporate that outcome as part of his campaign.

But Pinello predicted the level of attention to marriage would remain the same even if same-sex marriage were to resume in California because gay couples are already marrying in other places within the United States.

“There’s nothing new about that,” Pinello said. “It’s happening in six or seven other jurisdictions presently. It already did happen in California with 18,000 couples in 2008. So, there’s really nothing new about that and I don’t see that having much of an impact other than very short-term coverage.”