“Operation Chaos” was coined by conservative talk show host Rush Limbaugh in March 2008, when he urged listeners to vote in the Democratic presidential primary for Hillary Clinton against Barack Obama. Limbaugh desired to cause “chaos” by making the Democratic primary disruptive, although he had no plans to endorse the Democratic primary winner. On October 22, 2010, Limbaugh announced “Reverse Operation Chaos” (not “Operation Reverse Chaos,” as in Wikipedia), urging Clinton Democrats to stay home for the November 2010 election.
 
On January 3, 2012, Limbaugh declared that “Operation Chaos” had entered the lexicon. “Operation Chaos” means any party that causes “choas” or disruption in another party’s primary election.
 
 
Wikipedia: The Rush Limbaugh Show
The Rush Limbaugh Show (also called The Rush Limbaugh Program) is an American talk radio show hosted by Rush Limbaugh on Premiere Radio Networks. Since its inception on August 1, 1988, The Rush Limbaugh Show has become the highest-rated talk radio show in the United States.
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Operation Chaos
In late February 2008, Limbaugh announced “Operation Chaos,” a political call to action with the initial plan to have voters of the Republican Party temporarily cross over to vote in the Democratic primary and vote for Hillary Clinton, who at the time was in the midst of losing eleven straight primary contests to Barack Obama. Limbaugh has also cited the open primary process in the early primary states of New Hampshire and South Carolina, which allowed independent voters to cross over into the Republican primaries to choose John McCain over more conservative candidates (such as Fred Thompson), as an inspiration.

At the point in which Limbaugh announced his gambit, Obama had seemed on the verge of clinching the Democratic nomination. However, Clinton subsequently won the Ohio primary and the Texas primary (while losing the Texas caucus and the overall delegate split) with large pluralities from rural counties; thus reemerging as a competitive opponent in the race. Statistics released by the state of Texas show Hillary Clinton won the primary due to a large number of Republicans crossing over to vote for her. Whether these voters were Operation Chaos Operatives or simply Republicans who preferred Clinton is impossible to tell.
 
On April 29, 2008 Limbaugh declared an “operational pause” in Operation Chaos, saying that Obama’s defeat in the 2008 Pennsylvania primary and fallout from statements from Obama ally Reverend Jeremiah Wright could have damaged his campaign to the extent superdelegates would shift to Clinton’s side. Determining Obama had weathered that storm, Limbaugh lifted the pause the next day and renewed his call for his listeners to vote for Clinton in the upcoming Indiana and North Carolina primaries. Obama won the North Carolina primary but was narrowly defeated in Indiana, where Clinton won decisively in rural counties that normally vote Republican in presidential elections.
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Limbaugh revived Operation Chaos with a twist in late October 2010 by urging Democratic voters who felt that Hillary Clinton was “screwed out of the nomination” to stay home and not vote. This has been coined by Limbaugh as Operation Reverse Chaos.
   
RushLimbaugh.com
Rush the Vote: Operation Chaos
March 12, 2008
RUSH: Operation Chaos. What did that black website name this yesterday? I’m having a mental block. The Rush Vote. Listen to this. This is from somebody by the name of John K. Wilson at the Huffington Post today. Headline: “Mississippi, ‘Limbaugh Effect’ Softens Blow for Hillary Clinton—Hillary Clinton suffered a huge defeat last night in Mississippi, and now faces an insurmountable pledged delegate lead by Barack Obama. But what most pundits missed was the fact that Obama’s victory would have been even more overwhelming in Mississippi (and he might have won the popular vote in Texas) if not for the ‘Limbaugh Effect’: Republicans voting in the Democratic primary in order to undermine Barack Obama and help John McCain. ... In the voting during January and February, Republicans were an average of 3.8% of the voters in the Democratic Primary, and they heavily supported Obama. But for the primaries in March, in Texas, Ohio, and Mississippi, Republicans have been 8% of the voters in the Democratic primary, and now they heavily support Hillary Clinton. This is definite proof of the ‘Limbaugh Effect’ coming through.”
 
14 March 2008, Washington (DC) Times, “Kingmaker”:
Mr. Limbaugh, calling it Operation Chaos, has urged listeners in primary states to vote for Mrs. Clinton to roil the Democratic race and keep it going.
 
RushLimbaugh.com
Reverse Operation Chaos in 2010: Clinton Democrats Must Stay Home
October 22, 2010
RUSH: Now, ladies and gentlemen, seriously, it is time for election strategy. Everybody sits around and waits for the predictable October Surprise. What will it be? Who will launch it, who will be the target, what will be the objective of the October Surprise? I would like to be the October Surprise. I would like to announce the October Surprise today: Reverse Operation Chaos. You remember the original Operation Chaos was at the end of the Democrat primaries, we’d already had our nominee, McCain was already chosen. Our defeat was sealed. So we wanted the Democrat primary to extend, to go on and on and on, A, so we would have some fun, B, to keep my audience engaged, getting them involved in it, and, C, to try to expose Obama to as many people as possible to counter the notion he was the messiah. So Operation Chaos suggested in remaining primary states that Republicans register in those states, since our primary was done, Republicans re-register as Democrats and vote for Mrs. Clinton to extend the Democrat primary. So we were given credit. Operation Chaos was given credit for Hillary’s narrow squeak of a win in Indiana and for her keeping it close in Texas and for making Pennsylvania relevant. So it’s time today, ladies and gentlemen, for I, me, El Rushbo, to announce Reverse Operation Chaos.
 
RushLimbaugh.com
“Operation Chaos” Enters the Lexicon
January 03, 2012
RUSH: The Democrats are doing their own version of Operation Chaos with Ron Paul. Here’s Erin Burnett talking about it. “Operation Chaos” has now entered the lexicon. I don’t even get credit for it anymore, but this is Erin Burnett last night on CNN (her show: “Erin Burnett Out Front,” as opposed to out back) and this is what she had to say.
 
BURNETT: The caucuses in Iowa. You can go in as a Democrat and you can go to the door and say, “I’m gonna become a Republican for tonight and I can go in and vote.” Always all kinds of conspiracy theories about how much of that will happen and whether there will be people from the other party trying to influence. “Operation Chaos,” we call it.
 
RUSH: No, YOU don’t; I do. What is this, “‘Operation Chaos,’ we call it”? So it has entered the lexicon. So now the Democrats are doing their own version of it. “‘Operation Chaos,’ we call it,” and they’re sending Democrats to caucus for Ron Paul