Not to put you on the spot, but what would your definition of "progressive" be? I ask that a lot and get different answers. I have been a proud Democrat my entire adult life and worked for social justice and for progress as a liberal, so I was surprised to find many Bernie-supporter progressives basically considered me to a conservative because I supported Hillary Clinton over Bernie Sanders for president. Nothing else mattered, only which candidate I supported.
I'd like to see your source for that. Did they further break down demographics by race. Did they also look at men? Do you remember?
Given that HRC and Bernie agreed on more than 90% of issues, I'd like to know what differentiates being a progressive vs a liberal. I thought the terms were pretty interchangeable. I consider myself both, but I voted for Clinton in the primaries and the general election. As far as I know, Clinton supported all of the social issues I do, and it sounds like (now) that Bernie and some of his followers actually consider social justice, including women's rights (the heart of what I thought it meant to be progressive), to be optional.
The reason why Republicans win presidential elections (not to mention controls the house, senate, and most of the governorships) is that, in most states people who don't agree with or benefit from all, or even most, of what the GOP stands for still vote for them. Why? I've no idea, but the fact that the GOP still engenders more brand loyalty, and can also attract disaffected moderates and liberals, suggests that the democrats are failing at something the GOP is succeeding at. Maybe a lot of it is just racism etc. and a bunch of scared old white people who stupidly think they can set the clock back to circa 1955. People are afraid, and fear appears to make people more conservative in some ways.
But neither party is doing a good job of addressing what can be done about the number one job killer--technology that increasingly requires fewer humans to do jobs at all levels of education and skill (even in the sciences). The GOP focuses on immigrants and (in Trump's case) globalization as culprits that are stealing US jobs, and the Democrats push the conversion of our public higher education system to vocational schools for STEM (something the GOP is happy to go along with, since their kids usually go to elite, private schools anyway, and it behooves them for "commoners" to be disposable worker bees who haven't been thought to think critically--aka been liberalized--in school). No one is really ready to rethink our concepts of wealth, work, and ownership and to step outside of the traditional "capitalist vs socialist" box.