“Firebagger”  (FireDogLake blog + teabagger) is a name for someone from the “hard left”  or “professional left” (as President Barack Obama’s press secretary Robert Gibbs said in August 2010 about political activists to the left of Obama). The term was coined by “Knoxville” on the blog FireDogLake on December 24, 2009. Many on the FDL blog prefer to be called “firepups” (or “firedogs”) rather than “firebaggers.”
 
The “firebagger” term was popularized in an August 2011 blog post by Spandan Chakrabarti of the People’s View.
   
 
Urban Dictionary
Firebagger
A person nominally of the political left viewed as excessively critical of President Barack Obama, especially if the tendency is to reflexively or obsessively criticize him and seemingly not other political figures. Etymology: Jane Hamsher’s popular, left-leaning FireDogLake blog was regarded by Democratic moderates as having gone around the bend in being hypercritical, such as when Hamsher appeared on Fox News to denounce Obama’s Health Care Bill, got involved with Neocon zealot Grover Norquist and even reportedly Tea Party activists. Thus, FireDogLake + Teabagger.
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by Overreach THIS! May 18, 2010
 
Balloon Juice Lexicon
Firebagger – Unfortunate portmanteau of FDL ‘Firepup’ and ‘Teabagger’, possibly coined by Firedoglake commenter Knoxville in December 2009 to celebrate the new anti-Obama partnership between Jane Hamsher and Grover Norquist: “How can anyone seriously support any president as he pulls tom-fuckery on the American people? I’d be more than happy if Obama were to fight for the common good and the best interests of the American people. But he’s not. Till he changes course – and till others in his base see that he’s screwing around for all the wrong reasons and screwing us all over in the process – I’ll speak out against him. Call me PUMA. Call me Firebagger. Call me the last true Progressive standing.” First nutpicked for Balloon Juice here, courtesy of commentor Midnight Marauder.
 
FireDogLake
Treasury Okays Unlimited Slush Fund For Fannie, Freddie
By: Jane Hamsher Thursday December 24, 2009 4:00 pm
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COMMENTS
Knoxville December 24th, 2009 at 5:05 pm 66In response to Kordo @ 55
I’m getting a whiff of that old PUMA-ish scent in the air…
 
During Bush’s second term, even most of his own base started to see that he was a failure. Too bad it took his base so long to realize the obvious. Why did it take them so long?
 
We, on the other hand, see what way too many in Obama’s base aren’t ready to see yet.
 
How can anyone seriously support any president as he pulls tom-fuckery on the American people? I’d be more than happy if Obama were to fight for the common good and the best interests of the American people. But he’s not. Till he changes course – and till others in his base see that he’s screwing around for all the wrong reasons and screwing us all over in the process – I’ll speak out against him.
 
Call me PUMA. Call me Firebagger. Call me the last true Progressive standing.
 
Osbourne Ink
Nixon Had A Word For People Like Jane Hamsher (UPDATE)
Dec 13, 2010
Jane the Hamsher is one of the cool kids, I realize; her front page status at Arianna’s place helps maintain her illusion of intellect and relevance.
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There is nothing “left” left about Hamsher. She is known as a firebagger, after the name of her website. But in Nixon’s time, she would have been called a ratfucker.
           
The People’s View
Paul Krugman is a Political Rookie. Or How Barack Obama Left John Boehner Holding the Teabag, Again.
Monday, August 01, 2011 |  Posted by Deaniac83 at 6:45 AM
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Now let’s get to the fun part: the triggers. The more than half-a-trillion in defense and security spending cut “trigger” for the Republicans will hardly earn a mention on the Firebagger Lefty blogosphere.
 
Balloon Juice
August 17, 2011 8:45 pm
I Hate That Name That We Came Up With For Ourselves
by John Cole
So apparently some campaign flack somewhere called out the professional left and called them firebaggers or something.
 
ABC News—“Political Punch” by Jake Tapper
Obama Campaign Email With Criticism of Krugman, Liberal Blogs Triggers Ire
August 17, 2011 8:50 PM
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Later, Chakrabarti, 28, says of the triggers, which include pain for both parties, “The more than half-a-trillion in defense and security spending cut ‘trigger’ for the Republicans will hardly earn a mention on the Firebagger Lefty blogosphere….”
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And, he says, agitation on the left against the compromise makes them increasingly look like the Tea Party.
 
“When I used the term firebagger, I meant people who are more interested in winning an ideological argument that they are in making policy progress,” Chakrabarti said.
 
POLITICO.com
August 17, 2011
Ben Smith
Coinage of the day: ‘Firebagger’
Amanda Terkel scoops a scathing blog item forwarded around by the Obama campaign’s New Mexico state director.
 
The best line:
 
The more than half-a-trillion in defense and security spending cut “trigger” for the Republicans will hardly earn a mention on the Firebagger Lefty blogosphere. Hell, it’s a trigger supposedly for the Republicans, and of course, there’s always It’sNotEnough-ism to cover it.

UPDATE: Actually, I’m not sure who coined it; the reference is to the progressive Firedoglake.
 
Newser
Obama Staffer Slams Krugman, Liberal Bloggers
NM campaign director blasts ‘Firebaggers’
By Rob Quinn,  Newser Staff
Posted Aug 18, 2011 3:22 AM CDT
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The blog post, by Spandan Chakrabarti of the People’s View, can be read in its entirety here. The term “Firebagger” appears to be an attempt to combine “Teabagger” and the leftist blog FireDogLake.
 
FireDogLake
Rock n Rollers: Krugman and The Firebaggers
By: Presumptuous Insect
Thursday August 18, 2011 3:26 am
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COMMENTS
openhope August 18th, 2011 at 4:37 am «
Oh, yeah. I’m a member[ $45], but I can’t quit my original $10 a month stipend because the FDL rocks!
I’m more partial to Firedog, Firepup. I don’t see myself as a Firebagger. Not fond of the term. Actually, I really dislike Firebagger because of the asshole, ignorant TeaBaggers I know personally. Just saying.
I don’t Bag.