RALEIGH, N.C. — Changes made to absentee voting procedures five years ago in North Carolina may have emboldened workers to run the type of illegal “ballot-harvesting” operation alleged to have been used in a disputed congressional race. That’s according to election experts and lawmakers. Some observers are concerned that the changes made it possible for more people to apply for absentee ballots. Then so-called harvesters could collect unsealed ballots and manipulate them or throw out ones from minority voters who might have otherwise gone to the polls. The heavily Republican Legislature crafted the 2013 law that scaled back some voting options amid a national GOP push for voter ID laws and other restrictions they said were aimed at preventing in-person voting fraud. Experts say that type of fraud is rare.