There are as many factions among Republicans in the upper chamber as in the House. Both chambers have to agree on the final product. It won’t be easy.

House Republicans were jubilant after muscling through President Donald Trump’s “big, beautiful” tax and immigration package by a single vote.

The bill increases the deduction limit for state and local taxes (Salt), a hugely important issue for a few Republican holdouts in some Democrat-controlled urban areas.

Senate Republicans pushed forward with a simple-majority vote late Wednesday to undo an electric vehicle mandate set by California, which Democrats and the nonpartisan Government Accountability Offic...