If Mike Pence and Tim Kaine have been practicing in the mirror for Tuesday's debate, they should be just fine when they take the stage at Longwood University. Based on the descriptions of former journalists who moderated previous debates involving the vice-presidential nominees, Pence and Kaine are basically the same person.

Their politics are not the same, of course. But two men who have served in Congress, governed their states and earned reputations for civility are stylistically similar in a debate setting. While last week's presidential debate between Donald Trump and Hillary Clinton was a study in contrasts, the contest between their running mates could leave voters seeing double.

For insight into the candidates' approaches, I spoke with Ken Owen, a former Indianapolis news anchor who moderated one of Pence's gubernatorial debates in 2012, and Jay Warren, a former TV anchor in Virginia who moderated one of Kaine's Senate debates in 2012.

Here is Warren's appraisal of Kaine: “Tim Kaine is viewed as Mr. Nice Guy. In fact, I even called him an adult Boy Scout in a profile story I did on him a few years back. There is a certain earnest quality about him, but that doesn't mean he is afraid to go on the attack when necessary — on the policy level, not the personal level.”

And here is Owen's take on Pence: “Mike Pence is a very nice guy. Whether you agree with him or not, you would say after meeting him that he's a very decent guy who looks you in the eye, remembers your name. The debate I moderated was a very civil affair. What would happen to Mike Pence if he were in a situation where he faced someone who was really nipping at his heels hard? I think he would be stern. I think he would go after that person with facts and not emotion.”

Swap the names in those quotes, and the characterizations still fit.

There is a wild-card element in Tuesday's debate: Kaine and Pence will not simply be representing themselves, as they have in other debates during their political careers. They will be acting as surrogates for their respective presidential candidates.

Warren believes Kaine's tenure as chairman of the Democratic National Committee, from 2009 to 2011, prepared him for the role.

“He knows how to carry someone else's water,” Warren said. “We saw him do that at the beginning of the Obama administration, when there was a need for him to go out there and play the partisan warrior. I think he comes at it perhaps more prepared than a senator who hasn't had that experience. I think he will be a good defender of Secretary Clinton.”

Pence, meanwhile, will be juggling his responsibility to Trump and his own ambitions, according to Owen.

“The stakes for Mike Pence are twofold,” Owen said. "No. 1, he clearly does not want to damage his running mate's chances. He needs to come off as supportive of the ticket, and yet the other challenge is to be somewhat of his own man. If things don't land jelly-side up in November for Donald Trump, Mike Pence is in a position you might not have imagined three months ago: He's right in the thick of people who will be mentioned, in terms of 2020 candidates.”

"I think Mike Pence has always had presidential ambitions,” Owen added. "I wouldn't call what he's done a short circuit to the process, but he has launched himself. He was a national conservative voice; he would pop up on Fox News and the usual places. But now he's in every living room. He has a chance to connect with people who have never spent any time with him."

Despite the parallels between Pence and Kaine, Warren said voters should not expect a dull debate.

"Some people are saying this is going to be completely boring or they're just going to be two nice guys," he said. "Sure, they're nice, but there are distinct policy differences that are going to be drawn. I think that we may see some fireworks."