The comedian Stephen Colbert flew down to Washington last week to parody the nation’s campaign finance laws. But there was a flaw in his plan: The campaign finance system already is a parody.

Standing on a platform outside the Federal Election Commission, Colbert boasted about how he had won the FEC’s blessing to create a “super PAC” to raise unlimited funds. “I do have one federal election law joke if you’d like to hear it,” the new head of Colbert Super PAC offered.

“Knock knock,” Colbert said.

“Who’s there?” responded the crowd of about 200.

“Unlimited union and corporate campaign contributions.”

“Unlimited union and corporate campaign contributions who?”

“That’s the thing,” Colbert said. “I don’t think I should have to tell you.”

Pretty good, as anonymous donor jokes go. The PAC man returned to his stump speech. “I do not accept limits on my free speech,” he said. “But I do accept Visa, MasterCard and American Express. Fifty dollars or less, please, because then I don’t have to keep a record of who gave it to me.”

Fifty bucks? Come on, Stephen: That’s petty cash.

Colbert set out to prove how flimsy the campaign finance limits have become since the Supreme Court’s Citizens United ruling, and the super PAC he created is egregious enough, allowing contributions of any size. But what he proposes to do isn’t nearly as abusive as what’s already going on. While Colbert’s PAC has to release the names of people who give him more than $200, the campaign finance vehicles preferred by people like Karl Rove allow individuals to give millions of dollars to elect candidates without the donors’ names becoming public.

The final structure of Colbert Super PAC is so limited that, campaign finance experts said, there was no need for him to seek permission from the FEC in the first place. And that’s the trouble: The real campaign-finance abuses are more horrible than Colbert’s fiction.

The Supreme Court, in five straight campaign-finance decisions, has largely wiped out the post-Watergate campaign reforms and, in the case of corporate contributions, undone nearly a century of law. Adding to the anarchy, Congress has been unable to agree on legislation requiring that donors be disclosed. For those who violate what’s left of the law, there is little risk of punishment, because the FEC, paralyzed by a partisan split, has been unable to agree on much enforcement.

“It has long been said that the FEC is designed to fail, and now it has,” says longtime campaign finance lawyer Brett Kappel. The result of all this, Kappel said, is “a very small number of extremely wealthy people can have an extraordinary effect on elections without being identified.”

Of the $5 billion or so expected to be spent on the 2012 federal elections, nearly $1 billion is likely to be of the unlimited “independent expenditure” type. The corporate cash tends to come from a small number of private businesses owned by extreme liberals or conservatives looking to elect like-minded candidates. This fuels the polarization that has brought Washington to a halt.

Colbert posed as if he were testing the limits of the law. He offered to give the FEC commissioners backrubs, and, on his Comedy Central show, likened them to Abercrombie & Fitch models. He came up with slogans suggestive of a fat-cat scam, such as: “Change is coming and I hope a lot of large bills, too,” and “It’s BYOB, Bring Your Own Billions.”

But when he sat at the FEC witness table, Colbert spoke no more than a sentence before the commissioners gave him their blessing (the one controversial element of his plan, involving Comedy Central parent Viacom’s role, was resolved the night before).

Out on the street, Colbert, escorted by officers from the Federal Protective Service, walked around with an iPad equipped with a credit-card reader. “Anybody else got a credit card?” he asked as he swiped. “Let’s charge it. You don’t mind if I sign for you, right? I’ll take the cash while I’m waiting. Oh, foreign money! Thank you very much.”

As a “Colbert Show” producer barked orders to her cameraman (“Gonzo, wide shot!”), Colbert remarked that Rove, who works for Fox News while also guiding the American Crossroads super PAC, should thank him for undermining the campaign-finance system. “I just made it perfectly above-board legal to talk about your super PAC on air and to use your corporate show to promote your super PAC in any way,” he said.

Alas, when it comes to making a mockery of campaign finance law, American Crossroads is way ahead of Colbert Nation.

Dana Milbank is an American political reporter and columnist for The Washington Post. Email to danamilbank@washpost.com.