"Obama's leftist policies"
Excuse me?
Which "leftist" policies would this be? Ramming through TPP? TTIP? Obamacare, which provides profit guarantees via the forced purchase of insurance? Chained CPI? The slow chipping away of Medicare? The huge handouts to rich financiers and the pathetic slaps on the wrist for the crimes they committed?
The only person who I'd have any hope of making any sea changes is Bernie Sanders, not because he is a Democrat, but because he's the only person in the US congress who can potentially stamp out the Democrat corporate lapdog contingent that currently rules the party (e.g. Nancy Pelosi and Obama) and turn it into something reasonable again.