While both campaigns have been lowering expectations ahead of Wednesday's first presidential debate, two of Mitt Romney's more notable surrogates raised the bar on Sunday, with one predicting Romney will turn the race "upside down."

Both New Jersey Gov. Chris Christie and Sen. John McCain said they expect Romney to shine when he shares the Denver stage for the first time with President Barack Obama.

"We have a candidate who is going to do extraordinarily well on Wednesday night," Chris Christie said on "Face the Nation" on CBS. The Republican governor said Romney will have his first chance to directly contrast his vision for the country with that of Obama.

"This whole race is going to be turned upside down come Thursday morning," Christie said.

McCain -- who has debated both Obama and Romney -- also predicted Romney will fare well this week. He said the debate will likely have more viewers than any other presidential showdown in history and argued that both candidates will "do excellent in their own way."

"I think you could argue that Mitt has had a lot more recent experience, obviously," McCain said on CNN's "State of the Union."

As the 2008 Republican presidential nominee, McCain battled Romney during the GOP primaries, then competed against Obama during the general election debates. While he foresees a record audience Wednesday night, McCain doesn't anticipate any major "breakthrough" moments from the debates, saying those have become far and few between in the last couple of decades.

"I can't remember the last time there was one of these comments that grabbed everybody's attention because, frankly, the candidates are too well prepared. They're well-scripted," the longtime senator said.

Political experts agree much is at stake in the first debate. Obama leads most national polls and has a significant advantage in polls in several key battleground states where the race is expected to be decided.

A number of political analysts have said that Romney's best chance of getting some momentum for his campaign will come in the debates, which stretch over most of October and leave two weeks of campaigning before Election Day.