The Senate voted 68 to 31 to proceed to debate on legislation to curb gun violence, beginning what observers expect to be weeks of argument on the most consequential congressional action on firearm regulations since the 1990s.

Sixteen Republicans joined 52 Democrats to approve a motion to proceed. Two Democrats joined 29 Republicans in opposing the motion.


"The hard work starts now," Senate Majority Leader Harry M. Reid (D-Nev.) said after the vote, noting that the Senate now faces potentially weeks of debate on the issue.

"There are powerful feelings about each of these proposals — both strong support and strong opposition," Reid said. "But whichever side you are on, we ought to be able to agree to engage in a thoughtful debate about these measures."

The White House expressed its full support for the process.

“There is still work to be done,” White House press secretary Jay Carney told reporters Thursday soon after the vote. “This was only, while important, a step in the right direction.”

Several family members of the victims of a mass shooting at Sandy Hook Elementary School in Newtown, Conn., watched the vote from the Senate gallery after spending most of the week lobbying senators of both parties to support the legislation.

Carney told reporters that Obama called Newtown families after the morning cloture vote. He said Obama congratulated -- and credited -- the families for the progress that the vote represents.

“With the vote we take today, we are turning the page. Against the NRA’s dominance, we are turning the page to do what is right by these families and by the American people,”  Sen. Charles E. Schumer (D-N.Y.) said at a news conference with the family members.

Turning to the families, Schumer said Newtown was the reason the Senate acted. “The only reason we are turning the page is because of you. You spoke to Congress. You spoke to the American people. We looked in your eyes, we saw your loss. We saw the hole where your child, your sibling, your parent used to be.”

Despite the vote to proceed, several Republicans said they would continue to oppose the legislation.

"The government should not punish or harass law-abiding citizens in the exercise of their Second Amendment rights," Senate Minority Mitch McConnell (R-Ky.) said.

The legislation under consideration "has that focus backwards," McConnell added.

Sen. John Cornyn (Tex.), the second-ranking Senate Republican, called the bill under consideration "a symbolic gesture" and said Congress should focus more on bolstering federal funding for mental-health programs: "We need to make sure that the mentally ill are getting the help they need, not guns."

The 16 Republicans who voted to proceed included Sens. Kelly Ayotte (N.H.), Lindsey O. Graham (S.C.) and John McCain (Ariz.), an influential trio on several policy issues. McCain had used an appearance on national television Sunday to protest a planned filibuster by conservative Republican senators, a move that earned praise on the Senate floor from Reid.

"John McCain has been a leader in this country for 31 years. People respect his opinion, and I’m grateful to all the Republicans who joined with us to allow this debate to go forward," Reid said.

The two Democrats who voted against proceeding, Mark Begich (Alaska) and Mark Pryor (Ark.), face difficult reelections in 2014.

"I think people should have the opportunity to vote if they know what they’re voting on," Begich said in an interview Thursday with the Daily News-Miner in Alaska. "I might be one of those that, at the end of the day, doesn't vote for cloture, because anyone can talk about amendments, but we haven’t seen one of them yet."

Other Democrats facing difficult reelections, including Sens. Max Baucus (Mont.), Kay Hagan (N.C.) and Mary Landrieu (La.) voted to debate the measure -- but haven't said whether they'll support the overall legislative package.

The measure up for consideration still contains largely Democratic proposals to expand background checks, make gun trafficking a federal crime and provide more federal dollars for school security programs.

But Reid said Thursday that the first amendment to be debated is a bipartisan agreement to expand the gun background-check program that was announced Wednesday by Sens. Joe Manchin III (D-W.Va.), Patrick J. Toomey (R-Pa.), Mark Kirk (R-Ill.) and Schumer. The agreement would extend the current background-check requirement from covering only sales at licensed dealerships to any sale that takes place at a gun show or that is advertised in print or online. However, checks would not be required for many sales between private individuals — a key concession by Democrats that gun-control advocates eagerly sought.

The proposal also would permit gun dealers to sell firearms across state lines, and gun owners with state-issued permits to carry concealed weapons would be allowed to take their firearms through states that don’t allow concealed weapons. The bipartisan agreement also calls for establishing a national commission to evaluate causes of mass violence.

Other proposed changes to the bill will come from members of both parties.

Sens. Patrick J. Leahy (D-Vt.) and Susan Collins (R-Maine) plan to introduce changes to the gun-trafficking provisions that would bolster legal protections for lawful gun owners who purchase weapons to give as gifts or raffle and contest prizes and are later used in a crime.

In a nod to groups seeking tighter gun restrictions, several Democratic senators plan to support amendments to ban military-style assault weapons and to limit the size of ammunition clips, but those measures are expected to fail. Another bipartisan group of senators plans to propose expanding programs that provide mental health assistance to military veterans returning from Iraq and Afghanistan.

Cornyn, a former state attorney general, is also seeking greater protections for prosecutors and law enforcement officers and may decide to re-introduce a bill he introduced Wednesday as an amendment to the gun bill.

Before the vote, several senators used personal stories of constituents to make their points. As they did on Wednesday, Sens. Christopher Murphy (D-Conn.) and Richard Blumenthal (D-Conn.) came to the Senate floor with large pictures of the victims of the Sandy Hook shooting.

But Sen. Mike Lee (R-Utah), who opposed moving ahead with the bill, read aloud from roughly 3,000 messages of support he has received in recent days. He read at length from a letter sent by a woman he said was named Emily, a 19-year old from Allentown, Pa.:

"Gun control doesn't solve anything, criminals will get guns no matter what. I want to protect myself as well as someone else. Please don't take away my Second Amendment rights."

Lee concluded: "Well said, Emily."

Aaron Davis contributed to this report.

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