The campaign trail can be a busy place, and it’s easy for well-intentioned candidates to make mistakes. Especially, it seems, for Sen. Barack Obama, who’s becoming (in)famous for refusing to admit to little gaffes. But he made one major error in his stop by an AFL-CIO sponsored event in Trenton, N.J.

Speaking to the crowd of union activists, Obama made the startling claim that the reason to pass the misnamed “Employee Free Choice Act” — a bill that would replace secret ballots with a process more known for intimidation than good manners — was the case of Atlantic City casino employees.

Whoa, Senator, hold your horses. If anything, the case of the Atlantic City casino “card check” victory was an embarassment. There are questions about one Congressman’s interference in the right to a secret ballot vote for the employees.

For Senator Obama, who certainly needs the plentiful pocketbooks of labor leaders, this was a gaffe, but by no means a little one.