DENVER — Four months after 26 people were gunned down inside a Newtown, Conn. school, the push for significant gun control legislation failed in Congress Wednesday, when a bipartisan amendment to expand federal background checks fell well short of the 60 vote threshold necessary to clear the Senate.

The amendment, sponsored by Sens. Joe Manchin, D-West Virginia, and Pat Toomey, R-Pennsylvania, went down on a vote of 54-46.

“This was a pretty shameful day for Washington, but this effort is not over,” said a visibly angry President Barack Obama, speaking in the White House Rose Garden 90 minutes after the vote as victims of gun violence, including former Arizona Congresswoman Gabby Giffords, looked on.

Obama blamed the gun lobby that “willfully lied” about the amendment and members of his own party who “caved to the pressure” and voted against the amendment.

Five Democrats voted against the measure, most of them representing more conservative states and facing uncertain reelection prospects next year (Majority Leader Harry Reid, D-Nevada, voted no for procedural reasons only so that he can re-introduce the amendment should it magically garner additional support).

Four Republicans voted in favor of the proposal, which would have closed the so-called “gun show loophole”, something Colorado did a decade ago, and require background checks for all online gun sales.

Those who opposed the proposal argued that it would lead to a federal registry of all firearms, something Democrats and even Republican Sen. John McCain, who voted yes on the amendment, dismissed as a scare tactic.

Colorado Sen. Mark Udall, a Democrat who faces reelection next year, issued a statement expressing his disappointment following the vote.

“I am disappointed that my colleagues could not come together and support this bipartisan background check legislation to prevent criminals and the mentally ill from obtaining guns,” Udall said.

“It’s a sad day for our nation when a minority of the U.S. Senate has blocked common-sense legislation that is supported by 90 percent of Americans. And Colorado gun owners, hunters and sportsmen understand that part of responsible gun ownership is ensuring that if you sell your firearm to someone else, that person is legally allowed to own it.”

Sen. Michael Bennet, D-Colorado, also voted for the amendment. Hours before the vote, Bennet told FOX31 that the amendment’s potential failure would be a shame.

“The special interests have gotten to it,” he said. “They’ve overtaken the voices of everyday Americans, of the familiies who have lost loved ones in this debate.”

The votes Tuesday afternoon are certain to be consequential for many of the lawmakers heading into next year’s midterm election.

“I believe we are going to get this done,” Obama said. “Sooner or later, we are going to get this right.”

New York City Mayor Michael Bloomberg, who’s spent millions in support of gun control legislation through his group Mayors Against Illegal Guns, doesn’t sound like he’s going away based on a blistering statement he issued following the vote.

“Even with some bi-partisan support, a common-sense public safety reform died in the U.S. Senate at the hands of those who are more interested in attempting to protect their own political careers – or some false sense of ideological purity – than protecting the lives of innocent Americans,” Bloomberg stated. “The only silver lining is that we now know who refuses to stand with the 90 percent of Americans – and in 2014, our ever-expanding coalition of supporters will work to make sure that voters don’t forget.”

Udall, Bennet vote against assault weapons ban

Knowing it had no chance of passage, Udall and Bennet both voted against a Democratic proposal to ban assault weapons, one of eight amendments to gun control legislation that was before the Senate Wednesday.

Immediately following the vote on the amendment brought by Sen. Dianne Feinstein, D-California, Udall’s office put out a statement.

“Coloradans, including sportsmen, hunters and responsible gun owners, agree that we need to keep dangerous military-style weapons off of our streets and out of places like our schools and movie theaters,” Udall stated. “In carefully studying the language of this specific assault weapons ban, it became clear that it went too far because it also would have banned certain hunting rifles and even some shotguns. And there was no opportunity to amend this legislation to make it work for Colorado sportsmen.

“While this legislation sought to keep the most dangerous weapons off of our streets, we needed a more tailored and measured approach that better respected our traditions of hunting, sport shooting and responsible gun ownership. More specifically, if this bill had been more carefully crafted to only ban weapons designed for the battlefield and keep them out of the hands of criminals and the mentally ill, I would have supported it.”