"Barack Obama is on our side," Ledbetter said. "It isn't a Republican or a Democratic issue, it's a fairness issue."

Obama, the U.S. senator from Illinois, is poised to become the Democratic presidential nominee.

Ledbetter won her suit over back pay in the lower courts, but her employer, Goodyear Tire, appealed all the way to the U.S. Supreme Court, which ruled 5-4 in its favor. The company successfully contended Ledbetter should have raised her concerns within six months of her first pay raise.

Justice Ruth Bader Ginsburg, in dissent, said the ruling "didn't make sense in the real world," Ledbetter said, "and she was right."

While she won't receive the pay she is due, Ledbetter said "we will receive a far richer reward if we secure fair pay for our children and our grandchildren."

"Equal pay for equal work is a fundamental American principle," she added. "We need leaders who will fight for it."