Here are five ways the Treasurer could boost revenue to make the numbers work.
The nation's biggest gun advocacy group operates as a bundle of distinct organizations. It's a fairly common arrangement, followed also by the likes of Planned Parenthood and the ACLU.
The lost incentives to give are likely to make a bigger difference than the small uptick in economic growth expected from the new law.
More than US$20 billion per year in giving is potentially at stake.
If Americans become less healthy and have less access to health care, then everyone loses.
Republicans rewriting the tax system have a rare opportunity to fix a major problem: most women-owned companies can't take advantage of key provisions designed to help small businesses like theirs.
With some tinkering, a federal tax credit that encourages developers to create new units that low-income Americans can afford to rent might yield other benefits.
The tax changes Trump and GOP lawmakers propose would reduce charitable giving, research suggests. But letting everyone use a tax break mostly enjoyed by the rich might prevent that.