William Cummings

USA TODAY

Donald Trump may be wishing he'd used one of the teleprompters he so often derides after his gaffe during a speech in Buffalo on the eve of the New York primary.

The Republican front-runner mistakenly referred to the convenience store chain 7-Eleven when speaking of the Sept. 11, 2001, terror attack on the World Trade Center.

"It's very close to my heart because I was down there and I watched our police and our firemen down on 7/11, down at the World Trade Center, right after it came down, and I saw the greatest people I've ever seen in action," Trump said. "I saw the bravest people I've ever seen, including the construction workers, including every person down there."

Trump didn't seem to notice the error and he went on to praise the "New York values" that his GOP rival Ted Cruz had referred to pejoratively earlier in the campaign.

Trump told the crowd it is those "values that makes us love this state despite its problems. We love this state. We know it's going to come back. If I am president, it's going to come back so fast you won't even believe it," he said.

Trump is heavily favored to win New York's primary Tuesday, and he desperately wants to take the state by a wide enough margin to sweep its 95 delegates.

New York’s primary: What we'll know and when we’ll know it