COLUMBIA — South Carolina voting rights advocates said Friday they are looking for voters who might not be able to have their votes counted next year under one of the nation's toughest voter identification laws.

The South Carolina Progressive Network is trying to identify some of the nearly 180,000 people who are now registered to vote but who lack the state- or federal-issued photographic identification called for under the new law. Those people would be able to cast provisional ballots, but would have to show the required identification within three days to have their votes counted.

South Carolina's history of discrimination against black voters means the photo identification law Republican Gov. Nikki Haley signed in June must get U.S. Justice Department approval. The initial public comment period for the new law runs through the end of August.

Supporters argued that the law was needed to head off voter fraud. Rep. Alan Clemmons, R-Myrtle Beach pushed the bill through the House. In a letter last month to the Justice Department he wrote, "First, let me say that it is an unspoken truth in South Carolina that election fraud exists."

But opponents Friday said there was no proof to back that up.

Democratic state Rep. Joe Neal argued against the measure as it moved through the Legislature this year. He noted supporters were never able to show that people were engaging in election fraud without a photo ID law. "There is not one case of voter impersonation that's gone to trial or been brought to court or been noted in this state," Neal said.

"This is a national effort to suppress the right to vote for the 2012 elections. That's the unspoken truth," Neal said.

Republican Gov. Nikki Haley stands behind the legislation she signed into law, said her spokesman Rob Godfrey. She "knows the voter ID law she signed this session was a critical step toward securing electoral integrity in our great state," he said.

The law requires voters to show a state Department of Motor Vehicles ID card or driver's license, a photo military ID, passport or a new state voter registration card that will have the voter's picture.

The state Election Commission says more than 178,000 voters lack a South Carolina driver's license or DMV photo ID. That represents 7 percent of the state's registered voters with 64 percent of them white and more than a quarter over 65.

At a news conference Friday, the South Carolina Progressive Network said it had voters on hand who lacked birth certificates or whose birth certificates aren't accepted by South Carolina.

California native Delores Freelon said her California birth certificate doesn't have her first name on it. "Because it doesn't have my first name on it, I'm not able to get South Carolina ID," Freelon said.

Freelon said her mother didn't provide a first name when was born and missed a deadline to add that to the birth certificate. Living on disability checks, Freelon, 59, said she can't afford to spend more than $700 to petition a court to change her name and it could take up to two years for California to make the change.

"I think it's wrong what they're doing," the Columbia woman said. "Sometimes one votes make a difference, so I won't even be able to make that difference nor will many more people who are in the same situation."

Larrie Butler, an 85-year-old Columbia native, said no birth certificate was issued for him when he was born in 1926. Now he can't get a South Carolina driver's. He said he had one in 1949 when he moved to Maryland, but when he moved back last year, South Carolina wouldn't issue him a license. "Of course, I will not be able to vote and the other thing, I won't be able to drive when my driver's license expires," Butler said.