Democratic leaders are considering advancing one of three background checks bills: a Democrat-only bill by New York Sen. Chuck Schumer — the “gold standard,” as one gun control advocate put it — goes forward to almost certain defeat; an alternative proposal by Sen. Tom Coburn (R-Okla.) without Democratic backing that calls for universal checks but includes wide exemptions for record-keeping added after pressure from gun rights groups; and a bill by Sen. Joe Manchin (D-W.Va.), which calls for expanding background checks and records requirements for commercial sales but not private ones.

Reid and top Democrats will decide which version to put forward, and the outlook there is far from certain.

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Up until now, Democrats have been unable to line up a conservative Republican to back a broad background checks bill. Manchin last week began negotiating with Toomey — a longtime ally of the powerful National Rifle Association — but as of now, no deal has been reached.

Manchin has until Tuesday to reach a compromise with Toomey for his expanded but not universal background checks bill. Since those talks began in earnest last Thursday, gun control and law enforcement groups have expressed their dismay over the possibility of ceding the universal checks that they — along with Obama and Vice President Joe Biden — have called for since Newtown.