WASHINGTON—The Senate passed sweeping revisions to the U.S. tax code past midnight Saturday after Republicans navigated a thicket of internal divisions over deficits and other issues to place their imprint on the economy.

The bill, which included about $1.4 trillion in tax cuts, would lower the corporate rate to 20% from 35%, reshape international business tax rules and temporarily lower individual taxes. It also touched other Republican goals, including opening the Arctic National Wildlife Refuge to oil drilling and repealing...