WASHINGTON -- California Attorney General Kamala Harris and unemployed consultant Jason Wonacott both earned their way into the Supreme Court for Tuesday’s oral arguments over gay marriage.

Wonacott’s way was more painful or, at least, wetter.

A Benicia, Calif., native and University of Washington graduate, Wonacott secured his seat in the courtroom by showing up outside at 10 a.m. Friday. He was number 13 in line, a place he held over four occasionally snowy days and nights, all to hear one hour of argument about California’s Proposition 8, which bans gay marriage.

“I’m gay,” explained Wonacott, who’s 25, “and I would like to get married someday.”

Harris and myriad other legal and political luminaries secured their seats through different means, though with equal enthusiasm. Seemingly everyone attending the arguments Tuesday morning in the case, called Hollingsworth v. Perry, anticipates seeing history in the making.

“It’s probably one of the most serious issues that will be dealt with by the court in a very long time,” Harris said Monday in an interview.

The Proposition 8 case marks the first time that the Supreme Court has considered whether the Constitution protects a right to gay marriage, and, if so, under what circumstances. While the case is remarkable enough on its own, it’ll be followed Wednesday by oral arguments over whether the Defense of Marriage Act improperly denies federal benefits to same-sex couples who are married under state law, in a case called United States v. Windsor.

Both cases have drawn widespread attention.

The justices must sort through about 90 friend-of-the-court briefs, as well as various extrajudicial efforts to sway opinion. On Monday, dozens of companies, from Amazon to Viacom, including such blue chip corporate institutions as Walt Disney, Goldman Sachs and CBS, took the unusual step of paying for full-page ads in The New York Times and The Washington Post to declare that “America’s leading businesses agree: Same-sex couples deserve to be treated equally.”

In front of the high court on snow-covered Capitol Hill, some people had paid others to hold their places in line since Friday in hopes of getting a chance to witness the hearing. One volunteer place-holder, Brigham Young University student Taylor Carter, said she’d showed up at 5 a.m. Saturday to hold a place for friends who were coming in from out of town.

Huddled beneath a tarp Monday morning against the wet snow that had fallen overnight, Carter said she’d probably never repeat the favor.

Both cases appear headed for close decisions, with the court split between liberals and conservatives. Both may be decided either narrowly or broadly. The Proposition 8 case, in particular, might be decided in a way that applies only to California, or to a handful of states in addition to California, or to all 50 states at once.

“They understand the debate that’s roiling in the country,” San Francisco City Attorney Dennis Herrera said in an interview Monday. “They recognize the importance of this issue.”

San Francisco officials propelled the debate by legalizing gay marriage in February 2004. Several thousand same-sex couples were married before the state Supreme Court blocked the city’s action. Herrera then sued to challenge the constitutionality of marriage laws that discriminate against same-sex couples.

The California Supreme Court recognized same-sex marriage rights in May 2008, after which about 18,000 same-sex couples were married. In November 2008, the state’s voters, by 52 to 48 percent, approved Proposition 8, which amended the California Constitution to declare that “only marriage between a man and a woman is valid or recognized” in the state.

The 9th U.S. Circuit Court of Appeals, in turn, struck down Proposition 8 in a way that didn’t affect other states. The appellate court, stressing the “unique and strictly limited” nature of its ruling, concluded in February 2012 that “the people may not employ the initiative power to single out a disfavored group for unequal treatment and strip them, without a legitimate justification, of a right as important as the right to marry.”

Three attorneys will argue the case. Charles Cooper, a former Reagan administration appointee who unsuccessfully argued on behalf of Proposition 8 during a San Francisco trial and at the appellate court, will make a return appearance. He’ll be opposed once more by Theodore Olson, a former Bush administration solicitor general. Speaking on behalf of the Obama administration, also in opposition to Proposition 8, will be Solicitor General Donald Verrilli.

The courtroom proper can seat about 400 spectators, in addition to 82 press seats in a hallway. Each of the attorneys who’s arguing receives six tickets. Olson, for instance, is using four of his for the two California couples whose names are on the lawsuit challenging Proposition 8.

Video: How Might Supreme Court Rule on Gay Marriage?

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