Rep. Jason Smith, the House’s new top tax writer, is promoting an approach he says would favor working-class Americans over large corporations, a shift in tone from his predecessors that raises questions about companies’ ability to push tax cuts through Congress.
It is from the Wall Street Journal.
I understand the passage as he is promoting an approach (and) he says (that the approach) would favor ...
If so, how can 'and' and 'that the approach' be omitted? If not so, how can I disassemble the passage to simpler parts to correctly understand?
Lastly, is it a usual expression?