WASHINGTON — The role of money and politics in the 2016 presidential election is a conundrum.

There will be humongous sums spent; the effect on the outcome could be minimal, but in time the flood of cash may produce Watergate-level money scandals.

Spending by candidates, parties and outside groups and individuals may approach $10 billion. Both Hillary Rodham Clinton and Jeb Bush, if they receive their parties’ nominations, each could spend more than $2 billion, about twice as much as Barack Obama and Mitt Romney forked out in 2012.

With several Supreme Court decisions lifting restrictions — on the misguided premise that money doesn’t buy political influence — the way is open for an orgy of spending by well-heeled interest groups and superrich individuals on both political sides. Even beneficiaries, including Mrs. Clinton and several top Republican aspirants, say the system is rotten.

Yet, unlike in the past, the money advantage may not be decisive. Among Democrats, Mrs. Clinton would dominate even without her overwhelming financial advantage; she would certainly be at least as competitive as a general election candidate.