Despite months of intense lobbying and significant public support, lawmakers failed to advance any gun control legislation through the Senate earlier this month. One by one, amendments came up for a vote in rapid succession, and one by one, they all failed. The hope that any gun bill would emerge from Washington seemed to go down with them.

Yet now, some lawmakers are quietly looking to revive the issue. According to the New York Times, at least two groups of senators are working independently on gun bills that would address separate issues: Background checks and gun trafficking. 

Given that gun legislation uniformly lost last time around, what do gun control proponents hope to achieve by circling back to the issue? Here's the Times' Jeremy W. Peters: 

Drawing on the lessons from battles in the 1980s and '90s over the Brady Bill, which failed in Congress several times before ultimately passing, gun control supporters believe they can prevail by working on a two-pronged strategy. First, they are identifying senators who might be willing to change their votes and support a background check system with fewer loopholes.

Second, they are looking to build a national campaign that would better harness overwhelming public support for universal background checks — which many national polls put at near 90 percent approval — to pressure lawmakers. [New York Times]

Sens. Joe Manchin (D-W.V.) and Pat Toomey (R-Pa.) are trying to breathe new life into their bipartisan background-check bill, searching for ways to attract the measly handful of votes by which it fell short the last time around. The Senate voted, 54-46, against that proposal earlier this month, with Senate Majority Leader Harry Reid (D-Nev.) joining the opposition solely so, through procedural rules, he could bring it back for another vote at a later date. Manchin told the Times he was considering tweaking the bill's language in a way that would give it the 60 necessary to override a filibuster from some of the GOP's more conservative members.

Aiding Manchin will be the intense lobbying efforts of several high-profile gun control groups. Mayors Against Illegal Guns, New York City Mayor Michael Bloomberg's (I) political action committee, has threatened to oppose Sen. Mark Pryor (D-Ark.) — one of only four Democratic senators to buck the party on background checks — when he comes up for re-election, in the hope that the threat will convince him to switch his stance. President Obama's Organizing for America has vowed to do the same with other Democratic lawmakers who vote no on bills to tighten the nation's gun laws.

Meanwhile, Americans for Responsible Solutions has already gone up with an ad targeting Republican Sens. Kelly Ayotte (N.H.) and Mitch McConnell (Ky.) That group, created by former Rep. Gabrielle Giffords (D-Ariz.), who was critically wounded and nearly killed in a mass shooting in Arizona, has focused its efforts solely on Republican senators for now.

At the same time, new polling data may also help stricter gun bills gain newfound support. A Public Policy Polling survey released this week found that Ayotte's approval rating had fallen by 15 points since October, settling at 44 percent. That offered some encouragement to gun control supporters who've said they believe a voter backlash will convince dissenting senators to change their minds.

On the flip side, a recent Quinnipiac poll found Toomey's approval rating rising amid his push for the background check bill, with 70 percent of voters in his home state saying they "strongly support" that measure. That's significant because polling in Pennsylvania can, to some degree, be extrapolated to other purple states.

The Washington Post's Greg Sargent explains:

Pennsylvania is an interesting test case with broader implications. While it does lean blue, it has a deep gun culture, and it is home to the sort of suburban district — represented by Republicans — where gun reformers still hope to pick up unexpected GOP support.

Indeed, one notable finding is that Pat Toomey’s approval rating is now at 53 percent among suburban voters — in a state where the Philadelphia suburbs are key to statewide races. Hopefully other Republicans who represent rapidly suburbanizing states (such as Kelly Ayotte) or suburban House districts will take note. [Washington Post]

While none of this means gun control bills are destined to ultimately pass, it shows that the debate is at least far from over. If nothing else, the Senate leadership has said they plan to readdress the issue this year. 

"I think we're going to bring this bill back before the end of the year and I think you may find some changes," Sen. Chuck Schumer (D-N.Y.) said Thursday.