This kind of action should be considered a simple courtesy. Of the 221 co-sponsors of the legislation, only 19 are Republicans. Democratic Representative John Larson (CT) sent House Speaker John Boehner (R-OH) a letter last Friday requesting a vote on the resolution.
Do Republicans Deserve Catholic Support? by Rachel Lu. (Crisis Magazine, 2/21/2014)
Yet another reason has just been shared. Although I have consistently voted Republican throughout my adult life, I preferred to stress to friends and relatives that I was a Catholic and a philosopher, but that I had no special loyalty to any political party. Evidently this attitude is common among young people today. I also find it to be quite common among faithful Catholics I know, many of whom resent the Republican Party for one reason or another.