>I suspect that that may just be a tactic to save face in vulnerable districts rather than a sincere desire to oppose the bill.

And the only reason Democrats voted against it was a tactic to save face for their constituents back home.

Why in the world would you think some politicians are magically sincere while others are not just by the little letter in parenthesis after their name?

Hyper partisan people that think this way are the reason political discourse has gone to shit and everything turns into some childish red team vs blue team ideology. As you keep propagating this mindset, people on both sides keep turning up the volume on their echo chamber and we get the most partisan congress (on both sides) in a hundred years[1].

1. https://www.washingtonpost.com/news/the-fix/wp/2016/01/13/he...

That's a good point. Are the Republicans who voted against the bill relatively unpopular with their constituencies?

Hard won congressional seats will often sit out or sometimes even vote against their parties legislation but coordinate their votes inch a way that ensures that their parties legislation still passes.

Say you have 54 democrats in the senate, and a democratic president 4 democrats that had difficult races can abstain or vote against the bill while 50 democrats can vote for it, with the vice president being the tiebreaker.

As far as I know Justin Amash is well liked within his district.