Hawaii's governor planned to sign a bill legalising gay marriage in the state that kicked off a national discussion of the issue more than two decades ago.
Now the island chain is positioning itself for an increase in tourism as visitors arrive to take advantage of the new law.
"In Hawaii, we believe in fairness, justice and human equality," Gov. Neil Abercrombie said after the state Senate passed the bill. "Today, we celebrate our diversity defining us rather than dividing us."
Hawaii's gay marriage debate began in 1990 when two women applied for a marriage license, leading to a court battle and a 1993 state Supreme Court decision that said their rights to equal protection were violated by not letting them marry.
That helped lead Congress to pass the federal Defense of Marriage Act in 1996, which denied federal benefits to gay couples.
The US Supreme Court struck down part of the act this year, declaring unconstitutional a provision restricting the words "marriage" and "spouse" to apply only to heterosexual unions.
The decision led Abercrombie to call a special session that produced Hawaii's gay marriage law.
The law allows gay couples living in Hawaii, and tourists from other states, to marry in the state starting Dec. 2. Another 14 states and the District of Columbia already allow same-sex marriage. A bill is awaiting the governor's signature in Illinois.
President Barack Obama, who grew up in Hawaii, praised passage of the state's bill, saying the affirmation of freedom and equality makes the country stronger.
An estimate from a University of Hawaii researcher says gay marriage will boost tourism by USD$217 million over the next three years, as Hawaii becomes a destination for couples in other states.