As usual. It implies that the views of 'average Americans' are abrogated by the economic elite. As the PDF clearly states on page 14 "It turns out, in fact, that the preferences of average citizens are positively and fairly highly correlated, across issues, with the preferences of the economic elites." It also turns out that the paper defines 'average American' as someone at the 50% income level, and 'economic elite' as someone at the 90% income level or above, which works out to $146,000. The paper than argues that this 'elite' population fairly represents the truly elite (the top 2%) based on 13 policy preference questions--which aren't listed in the paper--with a correlation of r=0.91 vs a correlation of r=0.69 for the 'average' population.
Sorry. There ain't nothing in this paper about the Koch brothers, Soros, Oprah, Bill Gates, or any of your other favorite elites. This is all about Joe the Plumber vs your mid-level Google executive.
So how does the paper define the views of the 'average American'? Well, on page 15, there's this "Some particular U.S. membership organizations--especially the AARP and labor unions--do tend to favor the same policies as average citizens. But other membership groups take stands that are unrelated (pro-life and pro-choice groups) or negatively related (gun owners) to what the average American wants." A footnote 40 then directs you to another paper by one of the same authors, presumably for the corroborating data.
Finally, on page 18, we encounter this: "Because of the impediments to majority rule that were deliberately built into the U.S. political system--federalism, separation of powers, bicameralism--together with further impediments due to anti-majoritarian congressional rules and procedures, the system has a substantial status quo bias. Thus when popular majorities favor the status quo, opposing a given policy change, they are likely to get their way; but when a majority--even a very large majority--of the public favors change, it is not likely to get what it wants."
In other words, here's the real summary: "Elite academic researchers at elite universities have conducted a study in which they find that the constitutional system put in place by the founders of the republic to prevent mob rule is thwarting their elite progressive agenda by working as intended. Oh, and throwing a lot of money around and making noise tends to draw attention to your cause, particularly when it aligns with the majority view, which it does most of the time."
Nothing to see here. Move on.