Updated at 3:17 p.m.

Sens. Kelly Ayotte (R-N.H.), Heidi Heitkamp (D-N.D.) and Mark Pryor (D-Ark.) announced Wednesday that they will vote against the gun control compromise spearheaded by Sens. Joe Manchin (D-W.Va.) and Pat Toomey (R-Pa.), all but assuring the measure won't pass.

Ayotte's office confirmed Wednesday morning that she will not vote for the amendment, making her what appears to be the 41st vote against it. Later, Heitkamp and Pryor became the first Democrats to come out publicly against it.