So, essentially, senators are debating what might replace it. The most popular option, at this point, has been the Manchin-Toomey compromise which would partially extend background checks to gun shows and Internet sales. But even that compromise is struggling to attract the 60 votes needed to break a filibuster—at the moment, only three Republicans have said they'd vote for it, and Joe Manchin III (D-W.Va.) has said he still doesn't have the votes.
Meanwhile, 20 or so Republicans are also offering up their own replacement amendment for the gun bill, which would provide more funding for gun-crime prosecutions, mental-health services, and school safety but avoid imposing new rules on gun ownership.
So, in order, here are the nine amendments that are on the calender:
1) Bipartisan legislation to expand background checks to gun shows and the Internet. This is the Manchin-Toomey proposal that's getting so much press lately. This amendment would essentially become the new gun bill if it passed. It would require all buyers of firearms at gun shows and over the Internet to complete federal background checks first. It would also strengthen laws against gun trafficking and straw purchases and provide funding for school safety.
This amendment, authored by Joe Manchin III (D-W.Va.) and Pat Toomey (R-Pa.), is considered the one with the best odds of passage, but it's still very far from a certainty. An analysis from my Washington Post colleagues Tuesday found that just 52 senators were planning on voting for the amendment — not enough to meet the 60-vote threshold to break a filibuster. One key person to watch will be John McCain (R-Ariz.) — he could be a swing vote.
2) A Republican substitute gun measure. This amendment, authored by Chuck Grassley (R-Iowa) and Ted Cruz (R-Tex.), would replace the current gun bill with a GOP alternative. Some of the details can be found in this backgrounder.
The basics: This bill would increase resources for gun prosecutions, mental health, and school security. It would also increase certain gun rights, such as allowing interstate handgun sales and giving members of the military more leeway to buy firearms. But it would not include any restrictions on gun ownership.
3) Tweaks to the provisions on trafficking and straw purchases. This amendment, authored by Patrick Leahy (D-Vt.) and Susan Collins (R-Maine), would solely focus on tweaking the language on trafficking and straw purchases.
As I explained here, various bipartisan proposals have been floating around the House and Senate to strengthen penalties against "straw purchasers"—people who buy guns legally and then give them to those who are prohibited from owning them. The Leahy-Collins version, which was crafted with the National Rifle Association, would also "ensure that lawful gun purchasers can buy firearms from licensed dealers to give as bona fide gifts."
4) Expand concealed-carry permits. This amendment, authored by John Cornyn (R-Tex.), "would guarantee the rights of gun owners to carry concealed weapons across state lines and within other states that also have concealed-carry laws." Many Democrats are flatly opposed to this bill.
5) An assault weapons ban. This amendment, authored by Dianne Feinstein (D-Calif.) would ban certain assault weapons and high-capacity magazines. It tries to strengthen some of the loopholes in the previous assault-weapons ban, which lasted from 1994 to 2004. I've written a fuller breakdown here.
This legislation, which has attracted a lot of press, is unlikely to garner 60 votes, although Harry Reid surprised reporters on Wednesday when he announced that he would vote for it.
6) Expand gun rights to veterans. Under current law, veterans who go to the Veterans Administration and are deemed unable to manage their own financial affairs are also barred from owning firearms. This amendment, authored by Richard Burr (R-N.C.), would "require a judicial authority" to decide whether those veterans are unable to own guns. The proposal, Burr says, could potentially affect some 116,000 veterans.
7) A ban on high-capacity magazines only. This is essentially a slimmed-down version of the assault-weapons ban and would focus solely on high-capacity clips. The amendment is authored by Frank Lautenberg (D-N.J.) and Richard Blumenthal (D-Conn.). You can check out the text of the proposal here, and Lautenberg explains the rationale behind the legislation in this op-ed.
8) Protect the privacy of gun owners. This amendment, authored by John Barrasso (R-Wyo.), would limit the ability of state governments to release the names of gun owners.
9) Funding for mental health programs. This amendment, authored by Tom Harkin (D-Iowa) and Lamar Alexander (R-Tenn.), would expand federal mental health programs on a variety of fronts, from schools to suicide prevention to "assessing barriers to integrating behavioral health and primary care." You can see a breakdown of the proposal here.