More than 20 years ago, a newly elected President Bill Clinton decided that overhauling the country’s loophole-ridden campaign fund-raising rules would be a top goal of his first year in office. Months later, faced with battles over health care and the deficit as well as opposition from lawmakers in his own party who had prospered under the old political-money regime, Mr. Clinton dropped the issue.

Instead, he became an adept fund-raiser and aggressive envelope-pusher, exploiting regulatory loopholes to raise hundreds of millions of dollars in so-called soft money for the Democratic Party, and eventually ensnaring himself in one of the most significant scandals of his presidency.

Now it is his wife’s turn to tackle the issue of big money in politics.

In Iowa this week, in the first public appearances of her second bid for president, Hillary Rodham Clinton said that one of her top priorities was to “fix our dysfunctional political system and get unaccountable money out of it once and for all, even if it takes a constitutional amendment.”

Her remarks came at a time when once again, lightly regulated money is flooding the political system, this time moving not through national parties but party-blessed “super PACs“ that — thanks to Citizens United and other court and regulatory decisions — can accept unlimited corporate, union and individual contributions.