New Jersey's Supreme Court ruled Wednesday that the state constitution guaranteed gay couples all the rights and benefits of marriage, except one: the word "marriage."

The 4-3 majority decision, written by Justice Barry T. Albin, reasons that by legally redefining marriage to include same-sex marriage, the court risked imposing its "personal value system on 8 1/2 million people."

Instead, the court gives New Jersey lawmakers six months to create the necessary statutes for same-sex partnerships that are legally equivalent to marriage. Legislators may choose whether the partnerships are called "marriage" -- or "civil unions," as in Vermont.

"The Legislature has played a major role, along with the courts, in ushering marriage into the modern era," Albin wrote. "The great engine for social change in this country has always been the democratic process. Although courts can ensure equal treatment, they cannot guarantee social acceptance, which must come through the evolving ethos of a maturing society."

After a series of discouraging legal setbacks, advocates of gay marriage looked to New Jersey as their best hope for an outright legal victory -- the first since Massachusetts' Supreme Judicial Court legalized gay marriage in 2003.

Most saw Wednesday's ruling as a split decision: a victory because it powerfully expands the rights of same-sex couples, and a loss because it does not guarantee full equality.

"This decision takes us from third-class citizens to second-class citizens. Nowhere near first-class," said Steven Goldstein, chairman of Garden State Equality. "We get to go from the back of the bus to the middle of the bus."

The justices unanimously called for full legal rights for gays and lesbians. "There is no rational basis for, on one hand, giving gays and lesbians full civil rights in their status as individuals, and, on the other, giving them an incomplete set of rights when they follow the inclination of their sexual orientation and enter into committed same-sex relationships," Albin wrote.

The decision also rejects the notion that children or families would be harmed by gay marriage, reasoning that "families are strengthened by encouraging monogamous relationships, whether heterosexual or homosexual."

But there was division on the question of whether the court should grant the right to marry. In a sharply worded dissenting opinion, Chief Justice Deborah T. Poritz said the plaintiffs did not seek a collection of rights, but "asked, simply, to be married."

"Labels set people apart as surely as physical separation on a bus or in school facilities. Labels are used to perpetuate prejudice about differences that, in this case, are embedded in the law," she wrote. "Ultimately the message is that what same-sex couples have is not as important or as significant as 'real' marriage."

After the Massachusetts court's ruling, many anticipated a legal domino effect, but instead supreme courts in several states have rejected gay marriage. In July, high courts in Washington and New York upheld state laws limiting marriage to one man and one woman.

An appeals court in California this month ruled against legalizing gay marriage, and the case has been appealed to the state Supreme Court. Briefs filed by Atty. Gen. Bill Lockyer have argued that California's domestic partnership law already guarantees gay couples substantially the same rights as married couples.

Meanwhile, 19 states have sought to preempt rulings in favor of same-sex marriage by explicitly banning the practice in their constitutions. Eight more states will vote Nov. 7 on statewide bans, and seven others are considering such a move.

James Dobson, founder of Focus on the Family, said in a statement that he hoped New Jersey's ruling would drive conservative voters to "recognize that their state may be only one court ruling away from being forced to accept gay marriage," and thus compel them to vote in November.

"Nothing less than the future of the American family hangs in the balance if we allow one-man, one-woman marriage to be redefined out of existence," he said. "And, make no mistake, that is precisely the outcome the New Jersey Supreme Court is aiming for with this decision."

GOP strategists have fretted about the turnout of social conservatives in the upcoming election because of the scandal involving former Rep. Mark Foley (R-Fla.) and a book describing top White House aides embracing religious conservatives in public while calling them "nuts" behind their backs.

"The Democrats don't want a divisive social or cultural issue to rise up right now and drive GOP turnout," said Republican pollster Frank Luntz. "Single-sex marriage is a proven driver of voter turnout. If it becomes an issue, cultural conservatives are sure to vote, and that's good news for the GOP."

But Joe Solmonese, president of the Human Rights Campaign, a national gay rights group, said he doubted that gay marriage would compel voters this year, when Americans are more focused on other domestic issues and the war in Iraq.