Yes you have hit what the Princeton study nailed. If it matters to the rich elites they get their way; this then leaves the remaining issues to the public to squabble over. Thus gun control, abortion, death penalty, etc all are left on the table. But if for some weird reason abortion became a profit engine for a Fortune 500 company then it would be taken off the table. [Following misspellings to avoid shill searches] Campaine Fineance reform, fud labeling, farmasootical reform, wired TeeVee reform, lowering rates for sellphone companies, halthcare ensurance company reform, guys-who-store-money reform, and my favorite: no eelectroonic vooting.
For any politician and especially party to genuinely take these on is pretty much the end of the show for them.
This is not an American phenomena. Just about all elections everywhere end up with politicians promising "Change" "Hope" or "A better future." But even if one party replaces the other the forces that put them there have the exact same agendas and thus nothing changes. Quite simply there are no billion dollar loobby groups fighting any of the above with vaguely the exception of eco groups who no longer seem to have the big domestic companies as their primary targets.