Advocates of stricter gun laws vowed Thursday to be louder and more passionate in the weeks and months ahead than gun-rights activists, who helped quash proposals to reduce gun violence this week that were widely popular among the public.

Working with a committed White House, gun-control proponents said they are mobilizing on two fronts. In the short term, they will attempt to shame opposing senators and stoke enough public outcry in their home states to force them to switch positions.

If that fails, they said, their long-term strategy is to help elect new ones.