That's a great point and would make and interesting USSC case. Until then though that's not legally considered a violation of separation of powers.
Barack Obama is center left. There is practically no such thing as a hard core leftist in the US Senate (someone in favor of a single payer health system--no private doctors, free education for all, aggressively progressive tax code, decriminalizing drugs and prostitution), maybe there are a couple in the House (I think there is one Socialist?). Don’t agree him on everything, but slightly more than Clinton (e.g., immigration, Iraq) and way more than McCain
