Right now he's trying to walk a line, praising the field collectively - "a lot of good people running" - while stepping more directly into the question of whether their policies or his are better for the country and good politics as well. The coming clash points are clear, as his day of campaigning in New Hampshire indicated.
At a Friday afternoon rally in Dover, he had commented about the state of the race and how he sees his own position in it. "The good news about being a front-runner is that you're the front-runner," he said. "The bad news about being a front-runner is everybody's behind you. You know what I mean. I'd rather be there than anywhere else. I get it. But you know, it's amazing."
Biden warned then, as he has before, about the danger of Democrats forming a circular firing squad, rather than keeping their focus on President Trump. And he seemed to cast himself as the most likely casualty if Democrats concentrated on tearing each other down. "I know I'm getting skewered by the quote New Democratic Party," he said, before quickly adding, "And I respect them, by the way."
Outside Annabelle's Natural Ice Cream shop in Portsmouth an hour or so later, his cone melting and dripping badly, Biden was asked about that skewering comment by CNN's Jeff Zeleny. "At what point do you plan to point out sharper differences between you and Sen. [Kamala] Harris and Sen. [Bernie] Sanders, on health care specifically?" Zeleny asked. "What are your differences with them?"
Profound differences," Biden responded. "I think that we should not be scrapping Obamacare; we should be building on it." Biden wants to add a public option to the Affordable Care Act, which would allow people to buy into a government plan if that's what they prefer.
"Took a long time to get us to where it is now," Biden said, adding a warning that too many people are at risk with their health to go through another prolonged debate over totally restructuring the system.
Sanders, Vt., Harris, Calif., Sen. Elizabeth Warren, Mass., and others in the Democratic field advocate scrapping the current system under the Affordable Care Act. They would replace it with a Medicare-for-all system that, eventually, would eliminate private, employer-based insurance. Some supplemental insurance likely would be available, just as it is today for those on the current Medicare system.
Biden argues that what his rivals are advocating is something far more complex that simply adding everyone on private insurance today to the current Medicare system. "It's not Medicare as you know it," he said. "The present Medicare system goes away. It's a brand new Medicare system. And so it is one that I think is going to be difficult to pass."
Biden credited Sanders at least with being upfront about the cost of a new program and the tax implications. "Bernie's been very honest about it," he said. "He said you have to raise taxes on the middle class. He says he's going to end all private insurance. I mean he was straightforward about it."
Sanders has said his plan would require increased taxes but argues that it would result in people paying less for their health care than under today's system.
Jonathan Martin of the New York Times asked Biden whether the other Democrats have been as honest as Sanders about the tax and cost implications of their plans. "So far not," he said. "So far not. They may. They may." He added, "I oppose the Republican Party trying to get rid of Obamacare . . . and I oppose Democrats who are" trying to do the same.
Asked specifically whether Harris has been clear on her position about eliminating private insurance under a Medicare-for-all plan, Biden grinned. "I'll let you guys make that judgment," he said.
Just how deep are Biden's differences with the others on the issue of health care? Is this a policy difference or does this go to the kind of campaign Democrats should run to maximize their chances of defeating President Trump in 2020?
Biden was asked directly whether Democrats can win a general election in 2020 if their nominee is advocating Medicare-for-all. He was clearly uncomfortable. He hesitated. He took a stab at answering, saying "well, look, I'm not going to," before pivoting back to safety by talking about the merits of keeping the current system and building on it.
He avoided a direct answer, but the question likely will come back to him as the campaign goes forward.
Biden also pushed back at Democrats who have criticized him for suggesting that, as president, he would try to work with Republicans and would seek compromises. That, in fact, was what prompted his reference to being skewered by what he called the "New Democratic Party." He knows he's been called naive for suggesting that the kind of legislating he did in the past could work in today's charged political climate.
In Dover, he pointed to the Constitution and indicated that he believes a president must respect the authority of the legislative branch and therefore work with lawmakers to enact legislation, rather than operating independently.
"We have a Constitution that says we have a separation of powers," he said. "I love my candidates I'm running with who would say to me, 'Trump is abusing the executive authority by using executive orders for things he has no right to do,' and then say, 'By the way, if I'm elected I'm going to issue an executive order to make sure the following things happen.' "
He did not mention Harris by name, but she has said if Congress does not move on gun legislation during her first 100 days in office, she would take action by executive order to do so. What Biden didn't note was the degree to which the man with whom he served under, President Barack Obama, turned to executive orders during his final years in office when he found his path blocked by the Republican-controlled Congress.
Biden can't afford another wobbly debate performance. He will defend his own positions in Detroit, but the question is how effectively he will challenge the ideas of others. If his views are as deeply felt as he suggests; if he believes in smaller steps on health care as the smartest course politically and in terms of policy; if he believes his rivals are the ones who are naive about how to make the system work, will he advocate that forcefully or tentatively?
In other words, will Biden be as strong an advocate for his positions as his leading rivals are for theirs?