MILWAUKEE (AP) -- Republican presidential contender Mitt Romney may have forgotten that Sunday was April Fools' Day.
His staff did not.
"This is a morning I'm not going to forget anytime soon," Romney told supporters a little later in the day. "They turned me into the April fool this morning."
Campaign workers took Romney to a room he thought was packed with supporters gathered for a pancake brunch. It was supposed to be his first campaign stop Sunday as he courted Wisconsin voters ahead of Tuesday's primary.
Romney said Rep. Paul Ryan walked out into the ballroom first and introduced Romney as he waited backstage with his newest supporter, Sen. Ron Johnson, R-Wis. There were the standard backstage cues for where to stand, along with Secret Service protection.
As Romney stood behind a black curtain, Ryan offered his usual enthusiastic endorsement, singing Romney's praises as applause filtered backstage.
His staff warned him not to expect a big crowd. That was an understatement.
Finally, it was time for Romney and Johnson to step into the room.
"The two of us go out there, and it's completely empty. There's nobody there," a smiling Romney said when his staff later brought him to the right room, where supporters had gathered, upstairs.
"Not only do they do that, but they caught it on camera," Romney said. "This is known as forgive, but remember."
Staffers plan to post a video of the prank on their blog.