Under a law that took effect Thursday in North Carolina, employees who issue marriage licenses can refuse to complete paperwork for gay couples by invoking their religious beliefs — a move that could mean longer waits at courthouses for all those who want to wed, especially in rural counties with small staffs.

Gay rights groups and some Democrats said legal challenges were likely to come soon for the new law, the second of its kind nationwide. Utah passed one this year.

North Carolina's law took effect as the state House voted to override Republican Gov. Pat McCrory's earlier veto. The Senate already had voted for the override. McCrory said though he believes marriage is between a man and a woman, no state employee should be able to break his or her government oath. His position puts him at odds with social conservatives aligned with his party.

Under the law, some register of deeds workers who assemble licenses and magistrates who solemnize civil marriages can decide to stop performing all marriages — for both straight and gay couples — if they hold a "sincerely held religious objection." Employees with a religious objection must stop performing all marriage duties for at least six months.

The chief District Court judge or the county register of deeds — both elected officials — would fill in on marriages if needed, but if enough staff members opt out, the issuing of all licenses in a county could fall to a single person.

Such a workload could mean longer waits or even days without anyone to issue licenses if the register is out sick, on vacation, or out of the office for work.

"There's certainly no way that an elected register, if they were the only person in the office issuing licenses, could be there 40 hours a week, every week," said Wayne Rash, the register of deeds for Caldwell County.

Of the state's 100 counties, 45 have three or fewer full-time employees in the register of deeds' office aside from the elected official.

"In a rural county that has only two or three employees, it will be problematic," said Drew Reisinger, who is Buncombe County's register of deeds and who opposes the law. "It is a very real scenario."

Lawyers for gay rights group Equality NC and the American Civil Liberties Union asked any same-sex couples who face difficulties to contact them.

Republicans supporting the measure said federal laws provided religious accommodations to government officials, in keeping with the U.S. and state constitutions.

Senate leader Phil Berger, R-Rockingham, introduced the bill shortly after federal rulings last October overturned North Carolina's voter-approved constitutional ban on gay marriage. Several magistrates had resigned after the state's top court administrator threatened reprimands, termination or charges for any who declined to officiate for same-sex couples.

One of the magistrates who resigned, Gilbert Breedlove of Swain County, said Thursday that he's pleased his former colleagues can recuse themselves without worrying about their jobs. He said his faith made him better at his job.

"I could bring my morals and integrity to the position instead of checking it at the door," he said.

But Shawn Long, who married his husband in October and was a plaintiff in one of the lawsuits that paved the way for gay marriages in the state, said the law is not about magistrates' religious freedom.

"They're using their religion to dictate what government services someone can get," he said.

Concerned Women for America accused McCrory of betraying state residents and forcing court officials to violate their consciences with the veto.

"It's hard to believe that any governor — much less a conservative one — would veto a bill protecting the religious freedoms of his constituents," North Carolina Values Coalition Executive Director Tami Fitzgerald said.