WASHINGTON -- In a hint of possible movement, one option that Schumer, Manchin and Kirk are considering would require background checks and record-keeping for private sales at gun shows and commercial sales online. It would exclude in-person, noncommercial transactions between people who know each other. The idea was described by two lobbyists and Senate aide who spoke on condition of anonymity to discuss private talks.

Other exclusions could include gun transactions between relatives and acquisitions by people with state-issued concealed carry permits, and there would be an online background check system for people in remote areas. Veterans officially determined to have some psychological problems would be given a way to appeal that decision, which would otherwise bar them from getting firearms.

Schumer has insisted on record-keeping for all private gun sales, saying the files are needed to keep the system effective. That led to stalemated talks with conservative leader Sen. Tom Coburn, R-Okla., who says the data would lead to federal records on gun owners.

If not included in the overall gun bill, an expansion of background checks could have been offered as an amendment. It likely would have needed support from 60 of the 100 senators to prevail - a difficult hurdle for Democrats.

"In order to be effective, any bill that passes the Senate must include background checks," Reid said in a written statement.

Gun control backers lauded the decision. Dan Gross, president of the Brady Campaign to Prevent Gun Violence, called it "a tremendous step and we recognize there is still a tough road ahead." He said his group would activate supporters to contact lawmakers.

"The majority leader's been a pretty steady guide throughout, and this a good example," said Mark Glaze, director of Mayors Against Illegal Guns, a group New York Mayor Michael Bloomberg helps lead.

Reid said that besides the assault weapons ban, he will allow votes on amendments including those related to high-capacity ammunition magazines and mental health. Many states poorly report mental health records to the federal background check system.