Casino Affiliate Programs that manage casinos that accept US Players:

CWC Partners
RTG powered online casino to market to the USA.
Intertops
Perfect US market package. Poker, RTG online casino and sports book is accepting all USA players. They've got skill games, too.
Main Street Affiliates
offers several online casinos to promote to the US market.
Best Casino Partner
Vegas Technology software powered casino that is accepting all US players to promote.
Commission Account
is mainly a online sports book affiliate program but their properties have online casinos , mobile gaming and online poker, too.

I know that there are other programs but those I the one I make money with.

Affiliate Programs