The wild card in the 2010 midterm campaign is spending -- specifically, unrestricted spending by corporations, trade groups, and labor unions. In its January decision in Citizens United v. Federal Election Commission, the Supreme Court overturned part of the McCain-Feingold campaign finance law as well as one of its own precedents in order to allow private groups to spend freely on campaigns right up to Election Day.

That means many incumbents may not be as safe as they look. For instance, in the January Field Poll of California voters, Democratic Sen. Barbara Boxer led each of her potential Republican challengers by at least 10 percentage points. But what's to stop corporate groups from spending huge amounts of money to defeat her? Nothing, according to the Supreme Court. The Court ruled 5-4 that corporations and unions have the same free-speech rights as individuals and can spend all the money they want to in trying to elect or defeat candidates.

Writing for the majority, Justice Anthony Kennedy declared, "This Court now concludes that independent expenditures, including those made by corporations, do not give rise to corruption or the appearance of corruption." The response from critics: What planet is he living on?

In 1990, the Court held that "corporate wealth can unfairly influence elections when it is deployed in the form of independent expenditures." The Court continued to hold that opinion as recently as 2003. Now that view has been cast aside in favor of a sweeping new interpretation that regards companies as people and money as speech.

President Obama, a former professor of constitutional law, denounced the ruling in his State of the Union address, saying, "The Supreme Court reversed a century of law that I believe will open the floodgates for special interests, including foreign corporations, to spend without limit in our elections." That drew a silently mouthed "not true" response from Justice Samuel Alito, who was sitting directly in front of the president.

Now Chief Justice John Roberts has joined the fray, questioning whether justices should attend the State of the Union address, which in his view has "degenerated into a political pep rally." Obama, who voted against confirming Roberts and Alito, has urged Congress to come up with "a forceful response to this [Citizens United] decision." We could be headed for a showdown, the likes of which have not been seen since President Franklin D. Roosevelt threatened to pack the Supreme Court with his own supporters.

FDR lost that fight. But in this case, public opinion is squarely with Obama. In an ABC News/Washington Post poll last month, 80 percent of Americans opposed the Court's decision, 65 percent of them "strongly." Opposition is bipartisan: 76 percent of Republicans and 85 percent of Democrats oppose the ruling. That's pure populism. The Supreme Court is the least populist institution of U.S. government. That is one reason some justices feel uncomfortable attending the State of the Union address. They want to remain insulated from politics.

Politicians used to have a place on the Supreme Court. Some of the country's most distinguished justices -- Charles Evans Hughes, William Howard Taft, Earl Warren -- once held elective office. In recent years, however, justices have come overwhelmingly from the "judicial monastery," that is, the lower courts.

The result is a high court that is often out of touch with political reality. Take, for example, its 1997 decision allowing the Paula Jones lawsuit against President Clinton to go forward. The Court declared, "It seems unlikely that a deluge of... litigation will ever engulf the presidency." Yes, well.

Now we are seeing open mockery of the Court. A Silver Spring, Md., public-relations firm is promoting itself as a candidate for Congress. Why not, if, as the Court says, companies have the same free-speech rights as persons? The campaign slogan? "Vote for Murray Hill Incorporated for Congress -- for the best democracy money can buy."

Meanwhile, Congress is considering a law that would help restore some balance by strengthening disclosure requirements to make sure that voters know who is financing campaign ads and to ban "pay-to-play" spending by companies that have government contracts, receive government bailouts, or are foreign-owned.

The Supreme Court has opened the floodgates for corporate spending in campaigns. The message to incumbents? No one is safe.

This article appeared in the Saturday, March 20, 2010 edition of National Journal.

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