The Machinists union said Friday its top national leadership has been re-elected “by more than a two-to-one margin” in the union’s first contested election in decades. That would be a victory for International Association of Machinists president Tom Buffenbarger, who’s led the union for 16 years.

The slate of challengers, known as IAM Reform, said Friday it would dispute the results, alleging the leadership illegally used union funds to campaign and intimidated lower union officials.

According to results posted on the IAM’s website, Buffenbarger received 23,545 votes while rival Jay Cronk had 11,163. Their combined total represents barely 6 percent of the union’s membership of more than 575,000.

The preliminary results are subject to certification by the Labor Department.