The "standing assumption" today is that "this is kind of the third rail of politics," Biden said. "That if you take this on, somehow, there will be a severe political price to pay for doing it. Because that's what's happened in the past."
The old rules no longer apply after the schoolhouse massacre in Newtown, Conn., Biden said, calling inaction on gun control "unacceptable."
"What I say to my colleagues ... I say to you, if you're concerned about your political survival, you should be concerned about the survival of our children," he said. "And guess what? I believe the price to be paid politically will be to those who refuse to act, who refuse to step forward. Because America has changed on this issue."
To a great extent, Biden's words were aimed directly at the National Rifle Association, which has largely stuck to its old playbook after Newtown, seemingly believing that its old strategy of rallying its grassroots base to punish pro-gun control politicians will work as it has in the past.
But gun control supporters have said for months that they're the ones with the political cards to play after the Sandy Hook school shooting, and there are signs that Democrats are starting to believe them.
Biden's speech mentioning the changing political landscape came on the same day as Greg Sargent interviewed Rep. Steve Israel (D-NY), chair of the Democratic Congressional Campaign Committee. Israel said the DCCC plans to put gun violence front-and-center in its efforts to retake the House in 2014.
"Both the minimum wage and reducing gun violence are priority issues in the districts we need to win," Israel told Sargent. "Both are a reminder to suburban independent voters that House Republicans are extreme, and out of touch. On both, House Republicans have rejected solutions and have embraced obstructionism, turning their backs on millions of hard working American families."
It's worth noting that polling backs up Biden and Israel as they make the claim guns are now a liability for the GOP rather than for Democrats. The public supports measures like universal background checks, the key component of the White House plan on gun violence. But it wasn't that long ago Democrats were keeping their distance from gun control, and the party hasn't used it as a central campaign plank in a long while. But Biden and Israel's statements Thursday appear to show a shift in thinking.