Bernie Sanders may be the outsider in the Democratic nomination race, but that doesn't mean he's a stranger to the debate stage.

Sanders (I-Vermont) has run for elected office more than a dozen times and is a veteran debater. As all eyes turn to Tuesday's first Democratic debate of the 2016 campaign, the big question is now: How will Sanders' fiery rhetoric and pointed platform play on the national stage?

"I think he's going to do very well," said Greg Guma, a Vermont-based journalist. “He is a strong debater. He will be speaking from the heart, from the basis of principles…he has fundamental positions that he does not equivocate on."





Guma said that another one of Sanders’ strengths is the ability to put opponents on the defensive by putting the issues in stark terms. “He has talked this year about how we are heading towards an oligarchy, and so, in a sense, he has said it is a choice between me and building a political movement to save the country or we’re heading toward oligarchy,” Guma explained. “Even the Democrat is in a sense put on the other side.”

While Sanders is seeking the Democratic Party nomination, he is technically an independent in Congress, which means he'll have more room to criticize Democrats and the party if it suits him.

Republican Richard Tarrant ran against Sanders and debated against him for the Vermont Senate seat in 2006, losing by more than 30 percent.

“I wouldn’t say he’s a bad debater at all,” Tarrant told ABC News. “Any time he gets stuck or you think you might have him in a corner, he slips out and he goes into his campaign stump.”

Tarrant also thinks that Sanders will do very well against front-runner Hillary Clinton. "I just don’t think she’s very quick on her feet,” he said. “But I don’t know if he’ll pull the punches because it’s a primary.”

It is unclear how much Sanders will go on the offensive. On the trail he often says he has never run a negative attack ad in his career. He shies away from -- and sometimes outright refuses -- to answer questions that he feels are too pointed at Clinton. On the other hand, he is willing to talk about differences between the two of them when it comes to their stance on policy.

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Guma thinks that is the key difference. “He is not, not going to ever say anything bad about a person,” Guma added, noting that Sanders makes a distinction between personal attacks and policy distinctions. “His campaign will be, ‘Hillary Clinton is a nice person, I like her, but where is she?’”

And then there’s the question of Sanders’ stump speech. Could it come across stale? Republican Mark Candon faced off against Sanders for the U.S. House race in 1998, when Sanders was running for his fourth term. Candon says Sanders’ fiery demeanor is typical for the campaign trail, but not necessarily the debate stage.

“He calls himself a socialist and no one has really called him on that,” Candon said.

“[Sanders] will certainly say the same things in the debate next week that he said in the debate in 1998,” continued Candon, a Republican rooting for a Rubio-Fiorina ticket. “He’s been in front of the cameras for a long time. He’s going to say the same thing -- that the billionaires are going to get all the money and everyone else is getting stuck and he’s going to do something about it.”

But Tarrant said that Sanders can get heated during debates, recalling a tense moment during his own Senate debate against Sanders in 2006.

“You have got to level with people on that one, Mr. Sanders,” Tarrant said on stage, wrapping up an attack on Social Security and pointing directly at Sanders. Sanders then stood up, pointed back at Tarrant and fired a response over the moderator's objections.

“I will level with people on that, because it’s people like you and...” Sanders started before a chorus of boos interrupted and the moderator regained control.

“The way to get him is to go right at him,” said Tarrant, who said he supports John Kasich for the Republican nomination.

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