Former New York City mayor Rudy Giuliani was in West Virginia on Monday, stumping for Republican John Raese, who’s locked in a tight U.S. Senate race against Democratic Gov. Joe Manchin.

As Giuliani calls in from the trail, I remind him that when we last met back in January, he was campaigning with Scott Brown on a bitter-cold morning in Boston’s Little Italy. “It seems like we’ve come a long way since January,” he chuckles. “The enthusiasm level is at the highest I’ve ever seen it.”

“What was going on in January has just gotten bigger and bigger — it’s gone nationwide,” Giuliani continues. “It is many things, but I believe that you can sum it up as Americans’ aversion to unlimited government — to government which they regard as out of control. That’s what I think is going on, and what’s at the core of the Tea Party movement.” That sentiment, he adds, is what will likely drive “those who may not describe themselves as Tea Party people but agree with its concerns” to the polls today.

Health care, Giuliani says, has been President Obama’s undoing. The former mayor sees Obama’s first-year push for a public option and more government control as the point when things began to unravel. “From the moment he took that approach, I thought for sure that he would start to come apart.”

As Americans grapple with the health-care issue, Giuliani acknowledges that some people hold “a certain desire to see everybody covered, out of fairness.” Still, he says, “there is an even stronger desire to make sure that we don’t become a socialized-medicine country — that however we are going to fix our problems, we don’t do it through socialized medicine, but do it through a more American, private-sector model.” Obama, he laments, “does not understand the second part of that,” and, before politics, “had never held a job where he’s accountable in his life.”

“I don’t think Obama understands, sufficiently, the American economy, to make the changes that are necessary,” Giuliani says. “I think he has a very warped view of the American economy that comes out of having been a Saul Alinsky–trained community organizer, which means years and years of believing that the best way to grow an economy is to attack the power structure — to attack business and create dependency programs.”