If your politics lists heavily to the starboard side, it’s likely that you are a little angry and surprised at the apparent reversal of ideology by Chief Justice John Roberts, who found a way to make “Obamacare” constitutional.

Hold on, the decision he engineered in the Citizens United case will unleash roaring rivers of secret cash, which could sweep away Obamacare and its authors in the 2012 elections for president and Congress.

It also could do serious damage to democracy by introducing governance by corporations and wealthy individuals whose names we will not know until they file their income-tax forms — well after the election.

Think of secret money on a hypothetical local level.

Two strong candidates have announced for mayor. One is a popular civic leader, known and respected throughout town and is the presumed frontrunner. The other is CEO of a large local industry about whom little is known.

Everyone assumes the civic leader will win in a walk until two weeks before the election when a torrent of advertising for the CEO gushes through the local paper, radio, TV and direct mail; suddenly, his smiling face is everywhere.

On Election Day, fleets of SUVs are seen all over town ferrying voters to the polls. The CEO wins by a landslide, and only later did citizens learn that the CEO, his company and other donors plan to drill for shale oil in city parks.

Outraged citizens and civic leaders can vote out the mayor in four years, but until then the city will be stymied by suits and countersuits and a secret ad campaign promising jobs and riches from “fracking” at popular parks.

Magnified to the national level, that is what the Citizens United ruling could make happen. Billionaires such as Las Vegas casino mogul Sheldon Adelson, who doesn’t give a damn who knows, plans to contribute as much as $100 million to influence 2012 elections.

Other corporations and billionaires for whom $10 million is chump change are allowed under the Citizens ruling to swamp the electoral process with secret money.

How did this happen?

It all began innocently enough. A non-profit, right-oriented company wanted to air a documentary critical of Mrs. Clinton, “Hillary: The Movie,” on pay-per-view TV during the final 30 days of the election.

The Federal Elections Commission found Citizens United in violation of the McCain-Feingold Act, which prohibited corporations from advocacy advertising on behalf of candidates in the last 30 days of campaigning.

Citizens appealed and argued narrowly before the Supreme Court that the law applied only to advertising, and not to documentaries.

Roberts assigned the case to himself and circulated a brief on those narrow grounds, but Justice Anthony Kennedy’s brief went further. He argued that corporations are persons who could never be prohibited from advocating pro or con, anytime they wanted under First Amendment rights to free speech.

When conservative justices flocked to the Kennedy draft, Roberts withdrew his brief and let Kennedy write for the Court, which drew protest from other justices that the chief had changed the rules on them.

Ever nimble, Roberts said to be fair that we’ll rehear the case (with five votes in his pocket) on the basis of the Kennedy draft. The court then went through the motions and ruled on the basis of the Kennedy draft.

“The new majority opinion transformed Citizens United into a vehicle for rewriting decades of constitutional law in a case where the lawyer had not even raised those issues,” wrote Jeffrey Toobin, the legal scholar and commentator in a long New Yorker article.

We now have judicial activism of the right, which is reminiscent of the Gilded Era when a corporation and a worker were equal partners in a contract, which allows the employee to work excessive hours for substandard wages.

The Civil War having settled the question whether the federal government was in charge or each of the several states could say what the law was, the Supreme Court turned its attention to protecting new wealth from regulation.

This court of the Gilded Era seems to be where Roberts’ judicial activism is leading.

In that era at the dawning of the 20th century, contracts were between co-equal persons, a corporation and a worker — and are sacred, said the court in those years. The court was protecting the workers’ contractural right to work intolerable hours for insufficient pay.

The Roberts court has loosed the dam of corporate contributions, which could overwhelm normal democracy downstream. Unless …

Unless President Obama and his campaign advisers can frame the election as a credible choice between a democratic government chosen on a level playing field or a government chosen by unnamed corporations and billionaires.

If American citizens see and believe that that is the choice, I believe popular will is stronger than even the tsunami of secret self-interest now being loosed.

H. Brandt Ayers is the publisher of The Star and chairman of Consolidated Publishing Co.