Those poll numbers directly reflect the influence of the richest Americans in support of unpopular policies that benefit themselves. America is broken because the American wannabe Aristocrats brought it down so that they personally could amass unimaginably large personal fortunes.
The interests of Aristocrats (and of Capital though Citizens United) are on the other side of all those popular policies that aren't implemented. Money can flood the system with bullshit, to paraphrase Steve Bannon, and defeat any proposals to undermine its power. Allowing anonymous free speech through political ads, which Citizens United did, opened our political system to any form of corruption someone wanted to fund. And they could do so with plausible deniability that it was them. This is how Capital can lobby and pass laws for anything, no matter how harmful those policies may be for the greater good. It's the worst possible perversion of our political system.