This is what they paid for. It's why they tolerate Trump damaging America's global position and the democratic norms at least some of them care about
And, like it or not, money helps win elections
No tax cuts would've left them disillusioned. They'd never vote Democrat, but they might choose not to volunteer. Or vote.
They'll celebrate this "win," and would've been discouraged by a loss.
That encourages volunteers and turnout, and reduces chances of primary challenges.
But how many of them will care?
The pain doesn't really kick in for a few years. And the media/politicians they trust will say it helps them. Most will believe it.
Passing a big tax cut that almost exclusively helps rich people will motivate them. But so would trying, but failing, to pass a big tax cut that almost exclusively helps rich people.
It's not regular order, which McCain said matters.
It's not close to deficit-neutral (even when assuming big economic growth), which Flake said matters.
It'll make premiums go up, which Collins said matters.
But the likely effect is a short-term boost. That's politically advantageous for 2018.
Maybe the bubble won't pop until after 2020. (If it does, they'll blame something else).
It's a terrible idea in the long-run. But the immediate effects should be pretty nice.
The policy is bad for millions of Americans and for the country as a whole.
But politically, passing it was better for Republicans than failure.