The Senate passed its version of the GOP tax plan shortly before 2 am Saturday morning on a narrow, mostly party-line vote of 51-49. Bob Corker was the only Republican to vote against it (here's why). The final bill — released online around 9:30 pm Friday — included hundreds of billions of dollars of changes designed to win over holdouts like Susan Collins, Jeff Flake, Ron Johnson, and Steve Daines.

What to expect: This vote is a done deal now, but the final version of what might be America's next tax code isn't. The Senate will still have to negotiate a final version with the House, but even though there will be critical details to be worked out, it's hard to see the bill falling apart after it's gotten this far.

Go deeper: What to watch for in the coming negotiations ... Why Republicans had to pass the bill