MARION, Iowa - After days of saying he would not make any predictions about where he will place in Tuesday night's caucus, this evening Mitt Romney declared "we're gonna win this thing."

"You guys, I need you tomorrow night, I need every single vote in this room, and I need you to get a couple of other vote from yours in your neighborhood and get to your caucus, I need a great showing in Cedar Rapids," said Romney, speaking at a rally at a Pate Asphalt warehouse, where more than 500 voters came to hear him speak.

"We're gonna win this thing with all of our passion and strength and do everything we can to get this campaign on the right track to go across the nation and to pick up other states and to get the ballots I need and the votes I need to become our nominee," he said. "That's what we're going to get."

A Romney campaign aide said immediately after the event that Romney was referring to winning the nomination, not tomorrow night's caucus.

Just yesterday, Romney waved off reporters asking him how confident he is going into the caucus, saying at press conference in Atlantic, Iowa, that he would not speculate about a Tuesday night winner.

"I'm encouraged that I was thought of positively by the people they called on the phone to take the polls," Romney said of the Des Moines Register poll released last weekend that has him leading the pack of GOP candidates. "I'm even more encouraged by the people I see at these rallies and at these events and the kind of enthusiasm they have."

"I can't tell you who's going to win this thing, but I do believe that I'm going to have a great deal of support and that will give me the kind of boost I need," Romney said.