Updated 7:51 p.m. ET

Senate leaders reached an agreement late Tuesday to hold up-or-down votes in the coming days on nine proposed changes to gun legislation under consideration.

Senate Majority Leader Harry M. Reid (D-Nev.) announced that the Senate will hold votes on a bipartisan proposal to expand gun background checks to cover most commercial gun sales, a proposal that still lacks sufficient support to pass.

Sen. Joe Manchin III (D-W. Va.). ( AP)

The Senate also will consider Democratic plans to ban military-style assault weapons and limit the size of ammunition magazines; and a bipartisan amendment that would make minor changes to the bill’s provisions regarding gun trafficking. Then, senators will consider four GOP-backed amendments, including a plan to permit gun owners who receives a permit to carry a concealed weapon in one state to do so in other states that issued concealed carry permits and other plans regarding the privacy of gun owners and funding for mental health programs.

All of the amendments will require the support of 60 senators to survive Senate procedural hurdles and be added to the underlying bill under consideration

The announcement came as the bipartisan background check proposal still lacked the votes needed late Tuesday to pass. Based on an analysis by The Washington Post, the amendment had the support of 52 senators as of midday Tuesday, with eight senators still undecided.

Despite the odds, Senate Democrats remained confident the measure would succeed.

"The American people deserve to stand on these important anti-violence proposals," Senate Majority Leader Harry M. Reid (D-Nev.) said Tuesday morning. He said that he is "optimistic and hopeful that cooperation from both sides will continue and that victims of gun violence will get the debate and the votes they deserve, including pro-gun advocates who want votes of their own."

In hopes of scoring more support for their plan, the background check plan's lead authors, Sens. Joe Manchin III (D-W. Va.) and Patrick Toomey (R-Pa.) met Tuesday with former Rep. Gabrielle Giffords (D-Ariz.) and her husband, Mark Kelly, who are leading a group pushing for new gun laws. Following a 15-minute meeting in Manchin's office, the senator escorted Giffords and Kelly to the weekly Senate Democratic luncheon.

Kelly and Giffords gave a brief presentation to the caucus lunch, drawing applause that could be heard from outside the closed-door meeting. A few minutes after entering, the couple left and tried to remain optimistic about the legislation’s chances, placing blame not on the contents of the bill but the way others are interpreting it.

“I don’t think it has so many problems. It’s been a short period of time, some folks need to read the legislation,” Kelly said, drawing out the word “read” for a point of emphasis.

Giffords and Kelly are also scheduled to attend an event Tuesday afternoon with Vice President Biden to formally dedicate a room in the Capitol Visitors Center named for Gabe Zimmerman, a former Giffords aide killed in the Jan. 2011 assassination attempt that wounded her and several others.

Among the senators undecided on how to vote on the Manchin-Toomey plan is Sen. John McCain (R-Ariz.), who said Tuesday that he is inclined to support it but is still awaiting more information on the plan's proposal to require background checks on Internet gun sales.

Winning McCain's support is considered essential, because he may provide political cover for other wavering Democrats and Republicans still uncertain on how to vote, according to Senate aides familiar with the process.

Manchin and Toomey also are considering the possibility of adding language that would exempt select far-flung communities in Alaska and North Dakota from some background check requirements, according to Senate aides familiar with the talks. Such exceptions could win the support of Alaska’s senators Mark Begich (D) and Lisa Murkowski (R) and North Dakota Democrat Heidi Heitkamp, a moderate with an A-rating from the NRA.

Spokespeople for Begich, Murkowski and Heitkamp said Tuesday that the senators remain undecided.

Republican senators opposed to new gun legislation continued to raise doubts Tuesday and called on Senate Democratic leaders to permit votes on GOP amendments.

"Background checks are not and never have been the 'sweet spot' of gun control debate," said Sen. Charles E. Grassley (R-Iowa). "We haven't voted on it because supporters don't have the votes to pass it, at least at this point. ... And I think they know it."

Grassley is working with other Republican senators on a GOP alternative to the underlying gun bill. Separately, Sen. John Cornyn (R-Texas) plans to introduce an amendment that would permit gun owners to carry concealed weapons from their home state into other states that also permit concealed carry. Only Illinois and the District of Columbia do not permit concealed carry privileges.

The concept of "national reciprocity" for concealed carry permits is popular in the closely-divided Senate, as similar proposals have passed in previous years. But gun control advocates have warned that Cornyn's proposal likely would kill any attempt to pass meaningful gun control legislation if it is successfully added to the bill.

Paul Kane contributed to this report.

Follow Ed O'Keefe on Twitter: @edatpost


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