It doesn’t happen. A commitment broken is death to any congressman. All types of retribution.
I consider a "yea" commitment is "eternal death". A sin to God by allowing this sinful bill (which contains just that) to be passed.
I believe, though, that if they go against the "regime" and flip their vote, they will have a chance to redeem themselves before God as well as the chance to save their seat in the House come November.