Has politics become a rich man's club?

After the 2016 election, I wondered if only the filthy rich would be able to run for president. Hillary Clinton, with a net worth of around $35 million, was the Democratic favorite, and her only challenger was Bernie Sanders.

Not being independently wealthy, Bernie had no choice but to fund his campaign with contributions. Hillary expected the contest to be a grand coronation, and was surprised Bernie put up as much resistance as he did.

On the Republican side, Trump with probably a little less than the $12 billion he claimed to have, was still able to use his own money to run rough shod over...