All right, I don't currently affiliate myself with either party mostly because no one in Washington actually gives a crap about doing what's right, but if you're curious to see far left financial policy failure, look at the current state of Illinois.
Since 1933, mayors of Chicago have been Democrat. Since 1982, Democrats have controlled the Illinois House of Representatives (except for 2 years). Democrats have controlled the Illinois Senate since 2003, and controlled the Governor's mansion from 2003-2014. NBC bragged that Illinois is the "most Democratic state in the country."
What we're left with is perhaps the most damning indictment of progressive economic policy--the AP reported recently that the entire Illinois revenue stream is now tied up in mandatory spending, meaning there is no money for school buses, domestic violence shelters, and ambulance services, just to name a few things. In fact, with recent court orders, the state can't even keep up with what the court's deemed mandatory. The list of now-broken promises made by Democratic politicians to Illinois residents over the past two decades is staggering. Their government, dominated by Democrats for decades, has utterly failed them. Sanders, Warren, and their buddies sure sound good on paper (who wouldn't want free college?) but Illinois (and Detroit for that matter) should serve as a stern warning.
Just raise taxes, right? Well, Democrats and GOP Governor Rauner are exploring that. But...they should keep in mind that for the third consecutive year, Illinois led the country in population loss, and will lose at least one electoral vote the next election cycle. Who would have thought people don't like seeing government take more of their money and flush it down the toilet, especially when they can move to a state with better weather and lower taxes in the Sun Belt (almost all of which are governed by the GOP). S&P and Moody's just downgraded Illinois's bond rating to "near junk" on June 1st, the lowest ever for a US state. Oh, and the south side of Chicago has become a war zone, but that's a whole other story.
Now I'm not suggesting trickle down economics is the answer either (see Kansas), but if we're talking about Democratic economic policy being best for the "common man," I kindly direct you to the above. Similarly, the reason why the Dems lost the Rust Belt this election, at least in my eyes isn't because of the promises crazy Donald made. In my mind it's more because of the failed promises the Obama administration made, and Hilary was far from trustworthy.