I've seen quite a few studies on money in elections. Most of them include non-competitive constituencies. Those that address ONLY competitive constituencies with competitive party registration numbers and two candidates that both receive reasonable amounts of money tend to fail to find any significant role of money in making a victor.
That doesn't mean campaign giving is useless: early fundraising can shut out primary challengers, or intimidate the other party into not competing in a meaningful fashion. And if you DON'T raise any money, then you don't fall into that category of "reasonable amounts of money." If the other guy raises $10 million and you raise $10,000, I don't see why you should expect to win: nobody apparently bothered to support your campaign. But if you raise, say, $1.8 million, and the other guy raises $4 million, it might make a big difference, but it also might not. Statistically, there's no clear indicator that such differences matter a great deal, in the one or two studies I've seen in my poli sci and econ classes. There may be others I haven't seen.
Racial allegiance actually wasn't a reference to Obama, but rather to some racial/ethnic groups tending to favor a specific party, such as African Americans with the Democratic Party (and possibly Hispanics). By religious influence, I meant election-day sermons and the like.
And making longer, staggered terms drastically reduces the returns on rent-seeking, because it means companies have constant election cycles to "buy," but politicians have comparatively much longer tenures and less need to worry about re-election. Possible methods that various peoples and governments have used to reduce rent seeking include geographic isolation (move the capital away from wherever all the lobbyists live), rigorous civil service examinations (which the US lacks), segmentation of interests (crush public sector unions, allow large firms to fail), constitutional limits or some other commitment mechanism (a credible claim to absolutely refuse to address a certain policy arena, meaning no firm has any incentive to lobby in regards to it), expansion of the powerful class (in the case of the US, this would men a larger congress), reinforcing the independence of institutions (changing the structure of political appointments, for example), and others.
Most of these options are not realistically on the table for most politicians. Which is sad, because those are the kinds of things that make real reform.
Ironically, the ECB is a fun example of how more completely independent institutions can curb rent-seeking. Is the ECB being lobbied? Yes, by many nations. But no Greek bank can really do much rent-seeking in a meaningful fashion, and the influence of any particular German bank is greatly limited. This inability to seek rents actually cripples many political systems that are built upon rent-seeking habits but, crucially, serves as a credible commitment mechanism. Supranational entities have a major democratic deficit, but sure are effective at being commitment mechanisms.
