Then as now, oligarchs were making their desires known.

A massive corporation controlled legislators and judges, and a commentator observed that "local folks now found themselves locked in the grip of a corporation controlled from Wall Street and insensitive to their concerns."

An expert testified before the U.S. Senate about "large sums of money that have been expended" on campaigns and how "many people have become so indifferent to voting."

A century ago, in the grand tradition of populist politics, Montana voters revolted against the "copper kings" and approved an initiative banning corporations from making "a contribution or an expenditure in connection with a candidate or a political committee that supports or opposes a candidate or a political party."

Montana's century-old restriction has become the focus of the latest battle over campaign finances. By a 5-2 vote, Montana's high court defied the U.S. Supreme Court and affirmed Montana's restrictive state campaign finance law.

The U.S. Supreme Court intervened in February, blocking the Montana decision from taking effect and citing the increasingly infamous Citizens United case, the 2010 ruling that brought federal politics back to the future by allowing unlimited corporate spending on independent campaigns in federal elections.

In the coming days or weeks, the high court is expected to revisit Citizens United, perhaps to summarily reverse the Montana court's decision, or, less likely, to grant review and revise the 2010 decision. We can hope.

Citizens United has upended federal elections, giving Republican candidates a significant money advantage. It will impact the presidential campaign and many congressional races.

Super PACs infused with corporate money almost certainly will be a factor in several California congressional campaigns, including Rep. Dan Lungren's race against Democratic challenger Ami Bera in Sacramento County, Rep. Jeff Denham's race against Democrat Jose Hernandez in the Modesto area, and perhaps Rep. John Garamendi's race against Republican Colusa County Supervisor Kim Vann in Yolo County and to the north.

Under Citizens United v. Federal Election Commission, unions and corporations can spend unlimited sums on independent campaigns. But billionaires and their corporate arms are dominating super PACs, and that's not likely to change.

The other day, Las Vegas casino mogul Sheldon Adelson erased lingering questions about which party has made the most of Citizens United by donating $10 million to the super PAC backing Mitt Romney, Restore Our Future. Counting Adelson, no fewer than 30 billionaires have donated to Restore Our Future, according to Forbes' latest count.

Restore Our Future raised $55 million as of last month, a number that will jump when the political action committee files its new monthly report today. At least 33 donors have given the committee at least $500,000, including 16 who have given $1 million or more.

President Barack Obama has big money donors, too. But there aren't as many and they haven't dug as deeply. Priorities USA, which supports Obama's re-election, raised $10.5 million as of its last report. Hollywood billionaire Jeffrey Katzenberg is its largest donor, at $2 million.

The Service Employees International Union has given $1 million to Priorities. With other unions, the SEIU has given six-figure donations to other super PACs. But so far in 2012, labor isn't keeping pace with donors to Republican-oriented committees.

The size of the donations and the ease with which the super-rich can hide their donations recall the pre-Watergate era when big donors secretly delivered millions to Richard Nixon's re-election campaign. Or Montana a century ago.

A few months after the Citizens United ruling, a Montana group called Western Tradition Partnership sued to invalidate Montana's law in a case that now is known as American Tradition Partnership v. Bullock.

In its pitch to donors, Western Tradition made no bones about its purpose: "You can give whatever you're comfortable with and make as big of an impact as you wish. Finally, we're not required to report the name or the amount of any contribution that we receive. So, if you decide to support this program, no politician, no bureaucrat and no radical environmentalist will ever know you helped make this program possible."

Montana Attorney General Steve Bullock, a Democrat who is running for governor, sees the issue as one of states' rights. The largest donation Bullock can accept for his run for governor is $630. The average state Senate race costs $17,000, less than the cost of a run for Davis City Council. It works for Montana.

"I don't think what we need is more undisclosed corporate donations," Bullock told me by phone.

Bullock also knows the issue goes far beyond Montana.

Justice Ruth Bader Ginsburg issued a note when the Supreme Court stayed the Montana case, pointing out that the Citizens United ruling resulted in "huge sums currently deployed to buy candidates' allegiance."

She was referring to forces seeking to elect the next president and Congress. In an earlier day, she might have been writing about the copper kings of Montana.