It benefits the lower income groups significantly while giving a kickstart to job growth, at nearly the sole expense of the upper middle class.

I don't like the plan because I pay more under it, but the value of the giveaways to the very rich seem rather small compared to low income benefits. Lowering of the corporate income tax rate and axing the mortgage interest deduction has broad support from economists across the political spectrum too.

NPR had an interesting piece on this in 2012:

https://www.npr.org/sections/money/2012/07/19/157047211/six-...

Edit, great chart showing who pays more / less: https://www.marketwatch.com/story/here-are-the-winners-and-l...

"while giving a kickstart to job growth" that's less than supported by evidence right now also at current level of unemployment it doesn't seem like taxes have been the limiting factor.

Our labor force participation rate has continued to drop, giving us a shrinking tax base. The official unemployment stat includes underemployed and part time workers as well, and is not fully reflective of the health of our economy.

Good article from Pew Research on this: http://www.pewresearch.org/fact-tank/2017/03/07/employment-v...

"As many observers have pointed out, the official unemployment definition leaves out some significant groups. The underemployed – part-time workers who would prefer to work full-time – are counted among the employed. And discouraged workers – people who’d like a job but have stopped looking because they don’t believe any work is available – aren’t counted as part of the labor force at all."