The Vermont senator told ABC's George Stephanopoulos on "This Week" Sunday that he would change parts of a bill that gave gun manufacturers immunity for crimes committed with firearms they made. It was supported by Sanders and opposed by then-Sen. Clinton.
But he wouldn't walk entirely away from it, even as he's hit from the left.
"I will vote to revise that bill. There are parts of it that made sense to me," Sanders said.
"Look George, if you have a small gun shop owner in Northern Vermont who sells a gun legally to somebody and then, you know, something happens to that guy, he goes nuts or something, and he kills somebody, should the gun shop owner be held liable? I think not," Sanders said.
"On the other hand, if you have a manufacturer that is sending guns into an area and really knows that those guns are not being used by the people or bought by the people in that area but are being sold to criminals, should we hold that manufacturer liable? Absolutely," he said.
Sanders added: "I am absolutely willing, as I've said for many, many weeks, if not months, to take another look at that piece of legislation."
His comments come as Sanders closes the gap with Clinton in Iowa -- where a new NBC News/Wall Street Journal/Marist poll
shows he's down just three percentage points -- and threatens to jeopardize Clinton's front-runner status by winning the first two states to vote in the nominating process.
Clinton has increasingly attacked Sanders in recent days, focusing on guns, Wall Street and the broader question of electability.
Sanders hit back on that topic, too, on Sunday.
"If people are concerned about electability, and Democrats should be very concerned, because we certainly do not want to see some right-wing extremist in the White House, I think Bernie Sanders is the candidate," Sanders said.
He pointed to recent polls that have showed him leading Republican candidates by a larger margin than Clinton in early voting states.
"We're doing much better with independents. We even draw a little bit better with Republicans," Sanders said.
"So I believe, quite honestly, that with the enthusiasm that we are generating, with the kind of voter turnout that I think we can bring out -- look, Republicans win when people are demoralized and the voter turnout is low," he said. "Democrats and progressives win when working people and low income people and young people get involved in the political process."