Conservative senators from both parties announced their support for expanding background checks for gun buyers Wednesday, giving a burst of momentum to supporters of stronger restrictions.
But big questions remain about whether President Barack Obama can push significant gun controls through Congress.
The compromise between Sens. Joe Manchin, D-W.Va., and Patrick Toomey, R-Pa., boosted the chances that the Senate will agree to broaden required background checks, a step gun control groups laud as an effective way to keep weapons from criminals and the mentally ill.
The senators are among the most conservative members of their parties, both have received "A" ratings from the National Rifle Association, and their endorsements could make it easier for hesitant colleagues to back the effort.