Some efforts to reduce gun violence face stiff opposition in the divided Congress.

The Senate Judiciary Committee approved bills to extend background checks on gun purchases and improve school safety Tuesday, but postponed consideration of a bill to ban certain kinds of assault weapons and high-capacity magazines.

The assault weapons ban was delayed to Thursday due to a conflict in Sen. Dianne Feinstein's schedule. Feinstein, D-Calif., is the lead sponsor of the ban.

The version of background check bill passed on party lines Tuesday but senators said it will be replaced on the Senate floor by a version developed by a bipartisan trio of senators.

Sen. Charles Schumer, D-N.Y., said he is working with Sens. Joe Manchin, D-W.Va., and Mark Kirk, R-Ill., on retooling the background check bill so that it might attract bipartisan support when it is considered on the Senate floor.

Sen. Tom Coburn, R-Okla., was originally part of the discussions but dropped out after an impasse over where records of private sales would be kept.

Sen. Chuck Grassley, R-Iowa, the ranking Republican on the Judiciary Committee, complained about the fact the bill wasn't ready and questioned the merits of marking up a bill that will not ever see a vote.

"We were told there was such widespread support for universal background checks that a bipartisan bill would be on its inevitable way to passage" said Grassley, who opposes universal background checks. "Instead, three of the four senators involved in those discussions do not endorse this bill.

Grassley also said expanding background checks to all gun purchases could lead to a federal registry of gun owners, a concerned shared by opponents of additional gun regulations.

Schumer firmly rejected the idea, telling Grassley that claims that universal background checks "will lead to national registration or confiscation… demeans the arguments" against the checks.

"The bill explicitly says there is no registration, explicitly says no confiscation," he said. "It's sad, right after Newtown there was a view that maybe the right place that we could all come together on was background checks."

A bill that would reauthorize $40 million in grants to improve school safety passed Tuesday with strong bipartisan support. Four Republicans joined the panel's 10 Democrats in approving the measure authored by Sen. Barbara Boxer, D-Calif.. Boxer initially proposed allotting $100 million dollars for the program, but scaled it back in order to get bipartisan support.

White House spokesman Jay Carney praised the committee's efforts during his briefing with reporters.

"Providing districts with resources to make their schools safer and closing loopholes that allow felons, the mentally ill, and others who should not have guns to avoid background checks are important measures that will help save lives," he said. "We look forward to continuing to work with Congress on this and on the other important pieces of legislation that are part of the president's comprehensive plan to reduce gun violence."

Last week, the panel voted 11-7 to approve a bill that would crack down on "straw" purchases of weapons by making the practice a crime. In such instances, people buy guns for those who are prohibited from doing so. The bill passed on a mostly party-line vote, with Grassley joining the panel's 10 Democrats to support the measure.

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