MANCHESTER, New Hampshire (Reuters) - New Hampshire on Wednesday became the sixth U.S. state to authorize gay marriage, deepening a New England niche for same-sex weddings and the spending that comes with them.

New Hampshire’s Democratic-controlled House of Representatives endorsed gay marriage in a 198-176 vote, hours after the state Senate approved the legislation 14-10 along party lines, making the state the fourth this year to back gay marriage in the United States.

Governor John Lynch, a Democrat, signed the bill, which goes into effect on January 1.

“Today, we are standing up for the liberties of same-sex couples by making clear that they will receive the same rights, responsibilities, and respect, under New Hampshire law,” Lynch said in a statement.

The law also recognizes out-of-state gay marriages and civil unions, which are legal in just a handful of U.S. states including New Hampshire. Same-sex couples who have civil unions in New Hampshire will automatically be married January 1, 2011.

Last month, the New Hampshire House rejected a similar bill. But Senate and House members met last week to approve new language giving clergy and religious institutions opposed to gay marriage greater protections, including the legal right to decline to marry same-sex couples.

Opponents, mostly religious conservatives, see gay marriage as a threat to the “traditional family” that is ordained by God and the foundation of civilization. Supporters often compare it to the path blazed by the civil rights movement.

PROTECTING RELIGIOUS BELIEFS

New Hampshire’s bill says religious organizations, associations or societies will have “exclusive control” over their religious “doctrines, teachings and beliefs”.

Organizations affiliated with religious groups that operate for charitable or educational purposes can deny marriage services to gay individuals, it adds.

“The (changes) strike the appropriate balance between two important values we believe New Hampshire residents support: equal rights for all and the rights to religious freedom,” said state Senator Deborah Reynolds, a Democrat.

Senate Republicans said the amendment did little to change a bill they oppose. Republican state Senator Sheila Roberge said Democrats should support Republican calls for a referendum so voters can decide the issue.

Only a few countries, mostly European nations, allow gay marriage. Forty-two U.S. states explicitly prohibit same-sex marriage, including 29 with constitutional amendments.

Last week, California’s supreme court backed a ban on gay marriage by upholding a voter-approved proposition defining marriage as between a man and a woman.

In stark contrast, gay-marriage laws are expanding swiftly on the East Coast, especially in New England where Massachusetts became the first state to allow gay people to marry five years ago.

Gay and lesbian weddings have boosted the Massachusetts economy by about $111 million, according to a study by the Williams Institute of the University of California.

Same-sex couples have been getting married in Connecticut since last year and in Iowa since April. Gay marriage laws in Vermont and Maine are due to take effect in September. The New York State Assembly passed a gay marriage bill last month, but it faces an uphill battle in the state Senate.

With the vote in New Hampshire, five out of six New England states now have passed legislation authorizing gay marriage, making Rhode Island with its large Roman Catholic population the region’s only hold-out.