The Obama administration will not drop its pursuit of tougher gun laws, Vice President Joe Biden vowed Tuesday, warning lawmakers who opposed earlier gun legislation of political hell to pay.

“The country has changed,” Biden, the administration’s point person on gun control, said at an event at the White House. “You will pay a political price for not getting engaged with dealing with gun safety.”

Two months after the Senate fell short of mustering the 60 votes it needed to advance a bipartisan proposal to expand background checks to firearms sales online or at gun shows, the administration has renewed its push for gun control.

The revived effort coincides with the six-month anniversary of the deadly Sandy Hook Elementary shooting in Newtown, Conn., the grisly massacre which prompted President Barack Obama to seek an overhaul of the nation’s gun laws in the first place.

Biden said that his message to gun control proponents was simple: “The president and I, our team, we have not given up.”

An April 17 vote in the Senate seemed to put gun control efforts to rest for the time being. Four Democrats joined 41 Republicans in a vote to block consideration of a compromise, scaled-back gun control proposal crafted by Sens. Joe Manchin, D-W.Va., and Pat Toomey, R-Pa.

“I am confident some of them — I know for a fact, some of them — wonder know whether that was a prudent vote,” Biden said of that vote, which saw the National Rifle Association do battle publicly with pro-gun control groups like Mayors Against Illegal Guns, which is backed by New York City Mayor Michael Bloomberg.

The weeks since then have seen those groups blanket key states and districts with radio and television ads looking to ratchet up pressure on lawmakers to either maintain or reverse their position on Manchin-Toomey.

To that end, as Biden spoke, Bloomberg’s group was making stop in Concord, N.H., as part of a bus tour in honor of the six-month anniversary of the shootings in Newtown, Conn.

The stop is designed to put pressure on New Hampshire Sen. Kelly Ayotte, R, who voted against a compromise to expand background checks.

Stephen Barton, a survivor from the Aurora theater massacre, and Vice President Joe Biden on the administration’s continued implementation of President Barack Obama’s plan to reduce gun violence.

Biden cited a “fundamental change in the political calculus” on guns, in which pro-gun control voters have mobilized, and will look to exact revenge against opposing lawmakers on Election Day.

“Look at those who voted no, and look at the pool results in their states immediately after they voted no,” he said.

And while Biden touted the administrative efforts undertaken by President Barack Obama to strengthen existing gun control enforcement, he said it was no excuse for congressional inaction.

“As proud as the president is of the progress we’ve made, we need Congress to act,” the vice president said. “The American people are demanding it.”