A funny thing happened on the way to the congressional switchboard earlier this week.

On Wednesday, Rush Limbaugh told his listeners to call Congress and tell them to vote no on health care reform. That’s no small thing. With his millions of fans, this is the kind of advice that could crash the congressional phone system.

But Rush made a critical error in his activism and it revealed an insider trick about grassroots organizing and showcased the absolute hatred some of Rush’s listeners feel about Democratic health care reform. Stay with me here – I promise the payoff will be worth it.

FamiliesUSA, a pro-reform activist group, has a toll-free number on its web site, telling supporters: “Call your elected officials at 1-888-876-6242. Tell them that Americans deserve better than the status quo. We need quality, affordable health care NOW.”

People who call this number, however, don’t actually reach elected officials – at first. They reach a recorded message that begins, “Thank you for calling your representatives and your senators. Please urge them to vote yes on health reform…” After the pro-reform message, the call is routed to the actual capitol switchboard. The purpose of this is to two-fold: To give callers a kind of script to say when they do reach members and senators and to spare them the cost of a long-distance call.

Unfortunately for Rush, he gave out the toll-free FamiliesUSA number on his show on Tuesday, which meant his anti-reform listeners got a pro-reform message when they tried to call Congress. So many Rush fans called the FamiliesUSA number on Tuesday that it caused a massive spike in call volume, which was immediately noticed by the group’s telephone re-routing vendor. Not wanting to pick up the tab for anti-reform calls, of course, FamiliesUSA immediately shut down the number and got a new one, which is posted above and now functioning as intended. (FamiliesUSA executive director Ron Pollack says the cost of that brief spike is in the thousands of dollars. “It’s an ironic form of flattery,” he quipped when I reached him earlier today.)

But Rush’s callers didn’t understand this whole re-routing thing and many were absolutely and astoundingly enraged. Many of them assumed the pro-reform message they got was a left-wing conspiracy to take over government. Think this is a stretch?

Here’s a Youtube video posted by one such caller, who believed he had discovered a blatant case of “Obama propoganda…Alert the patriots: Tyrants are ruining our country !”

He’s not alone. After FamiliesUSA turned off their original toll free number, it was bought by someone else who must have known about the mixup. That new person put a pro-reform bulletin on an answering machine and recorded messages left by angry – and I mean very angry – Rush listeners. WARNING: Many of the message contain obscenities – they can be accessed by calling 206-666-6666.

If you ever had any doubts that there are people out there who truly believe the Democratic health reform plan is a communist conspiracy to take over America…