Mitt Romney brought out the big guns in the battleground state of Ohio in the form of bombastic New Jersey Governor Chris Christie, who blasted Democrats for their excessive "BS."

Never one to shy away from a good barb, Christie took the stage before Republican nominee Romney and launched into attack mode against President Barack Obama and his party.

"A few weeks ago, I watched the Democratic National Convention. I did it as a sacrifice and service to my country," Christie quipped.

"I sat on my couch in my living room, and made my 12-year-old son Patrick bring me a big bottle of water, because I've gotta tell you, when I hear that much BS I can get dehydrated. I get lightheaded," he said to raucous cheers.

"I heard a lot of crazy stuff" from the early September confab, he added.

Christie, once a running mate prospect for Romney and a clear potential presidential candidate for 2016 or 2020, turned to a phrase Republicans widely mocked after it aired in a video at the Democratic gathering.

"They said 'government is the only thing we all belong to,'" Christie said.

"Even in my state, we talk this simple truth. We don't belong to government; the government belongs to us.

"The Constitution doesn't start 'We the government.' The Constitution starts off 'We the people.'"

With Romney enjoying a major boost in national and battleground polls since last week's debate in which he was widely seen as trouncing Obama, Christie is looking much like a soothsayer.

For weeks before that first debate, the campaign pumped out its message of diminished expectations for their candidate.

But on the weekend before the October 3 showdown, the New Jersey governor appeared to not get the memo, suggesting the face-to-face debate would be a time for Romney to show his presidential mettle.

"This whole race is going to turn upside down come Thursday morning," Christie said at the time.