I'm not aware of the exact income requirements for welfare, but we do have this exit poll data that suggests Trump did a little bit worse among poorer whites than middle class whites.
$<30,000: Trump 58; Clinton 34 (T +24)
30-49,999: Trump 56; Clinton 36 (T+20)
50-99,999: Trump 62; Clinton 34 (T+28)
100-199,999: Trump 56; Clinton 39 (T+17)
200-249,999: Trump 52; Clinton 44 (T+8)
>$250,000: Trump 50; Clinton 42 (T+8)
4 years ago, I think Obama won this demographic, or at least did better considerably on this demographic, than the average white voter, pre 08', this would've been a solid democrat constituency.
