One year ago, New York became the largest and most influential state where gay marriage is legal, raising supporters' hopes that it would boost national momentum and pump money into the state with a flurry of weddings from Manhattan to Niagara Falls.

As the anniversary nears Tuesday, the law's effects are noticeable if hard to measure.

Thousands of same-sex couples have wed across New York, but it's unclear just how many, partly because marriage applicants aren't required to identify themselves by gender. The wedding business is up, but some planners in New York City say it's not booming.

And while President Barack Obama announced support this year for gay marriage, no state has enacted a law allowing it since New York. And opponents note that North Carolina voters banned it.

California, which is almost double the size of New York, has been tied up in court over the issue since at least 2004 when the mayor of San Francisco ordered city clerks to issue licenses to gay couples and the subsequent popular vote in 2008 to ban same-sex marriages.