Former journalist Sidney Blumenthal has been widely credited with coining the term "vast right-wing conspiracy" used by Hillary Clinton in 1998 to describe the alliance of conservative media, think tanks, and political operatives that sought to destroy the Clinton White House where he worked as a high-level aide. A decade later, and now acting as a senior campaign advisor to Senator Clinton, Blumenthal is exploiting that same right-wing network to attack and discredit Barack Obama. And he's not hesitating to use the same sort of guilt-by-association tactics that have been the hallmark of the political right dating back to the McCarthy era.

Almost every day over the past six months, I have been the recipient of an email that attacks Obama's character, political views, electability, and real or manufactured associations. The original source of many of these hit pieces are virulent and sometimes extreme right-wing websites, bloggers, and publications. But they aren't being emailed out from some fringe right-wing group that somehow managed to get my email address. Instead, it is Sidney Blumenthal who, on a regular basis, methodically dispatches these email mudballs to an influential list of opinion shapers -- including journalists, former Clinton administration officials, academics, policy entrepreneurs, and think tankers -- in what is an obvious attempt to create an echo chamber that reverberates among talk shows, columnists, and Democratic Party funders and activists. One of the recipients of the Blumenthal email blast, himself a Clinton supporter, forwards the material to me and perhaps to others.

These attacks sent out by Blumenthal, long known for his fierce and combative loyalty to the Clintons, draw on a wide variety of sources to spread his Obama-bashing. Some of the pieces are culled from the mainstream media and include some reasoned swipes at Obama's policy and political positions.

But, rather remarkably for such a self-professed liberal operative like Blumenthal, a staggering number of the anti-Obama attacks he circulates derive from highly-ideological and militant right-wing sources such as the misnamed Accuracy in Media (AIM), The Weekly Standard, City Journal, The American Conservative, and The National Review.

To cite just one recent example, Blumenthal circulated an article taken from the fervently hard-right AIM website on February 18 entitled, "Obama's Communist Mentor" by Cliff Kincaid. Kincaid is a right-wing writer and activist, a longtime critic of the United Nations, whose group, America's Survival, has been funded by foundations controlled by conservative financier Richard Mellon Scaife, the same millionaire who helped fund attacks on the Clintons during their White House years. Scaife also funds AIM, the right-wing media "watchdog" group.

The Kincaid article that Blumenthal circulated sought to discredit Obama by linking him to an African-American poet and writer whom Obama knew while he was in high school in Hawaii. That writer, Frank Marshall Davis, was, Kincaid wrote, a member of the Communist Party. Supported by no tangible evidence, Kincaid claimed that Obama considered his relationship to Davis to be "almost like a son." In his memoir, Dreams from My Father, Obama wrote about meeting, during his teenage years, a writer named "Frank" who "had some modest notoriety once" and with whom he occasionally discussed poetry and politics. From this snippet, Kincaid weaves an incredulous tale that turns Davis into Obama's "mentor."

Kincaid's piece had been previously circulating within the right-wing blogosphere, but Blumenthal sought to inject the story into more respectable opinion circles by amplifying it in his email blast.

In the same piece, Kincaid, expanding his guilt-by-association tactics, also wrote that Obama "came into contact with more far-left political forces," including former Weather Underground member William Ayers. Until a few weeks ago, Obama's tangential connection with Ayers -- whose 1960s anti-war terrorism occurred when Obama was in grade school -- was echoing among right-wing bloggers.

Some Clinton supporters who also knew about Ayers have been discreetly trying to catapult the story out of the right-wing sandbox into the wider mainstream media. On April 9, Fox News' Sean Hannity interviewed fellow right-winger Karl Rove, who raised the Ayers-Obama connection. The next day, ABC News reporter Jake Tapper wrote about Ayers in his Political Punch blog. The following week, on his radio show, Hannity suggested to his guest, George Stephanopoulos, that he ask Obama about his relationship with Ayers at the upcoming Philadelphia presidential debate. Stephanopoulos, who was Bill Clinton's press secretary, replied, "Well, I'm taking notes." The following night during the April 16 nationally televised Presidential debate, Stephanopoulos dutifully asked Obama about Ayers, who is now a professor of education at the University of Illinois at Chicago.

One can only speculate how much influence Blumenthal did or did not have in elevating the Ayers story into the mainstream media and into the national political debate. What is certain is that Blumenthal sought to keep this classic red-baiting controversy alive.

Blumenthal's April 24 email dispatch featured a two-year old article by Sol Stern, published in City Journal, sponsored by the right-wing Manhattan Institute. The article, from the journal's Summer 2006 issue, doesn't mention Obama. Why would Blumenthal resurrect it now? The article, entitled "The Ed Schools' Latest--and Worst--Humbug," was, instead, a frontal attack on Ayers' views on educational theory and policy. Blumenthal obviously wasn't trying to offer enlightenment on educational policy or Obama's positions on school reform as much as he was presumably trying to keep Ayers' name, and his controversial past, in the public eye.

As a follow-up punch, Blumenthal again dipped directly into the "vast right wing conspiracy" by retrieving and circulating an article from the current issue of National Review -- the staunchly conservative opinion journal founded by William F. Buckley. The piece, titled "The Obama Way," was penned by Fred Siegel who, like Sol Stern, is a former 60s leftist who has moved to the opposite end of the political spectrum, serving at one point as a political advisor to Rudy Giuliani. Siegel's piece links Obama to corrupt Chicago machine politics, observing that "Blacks adapted to both the tribalism and the corrupt patronage politics" of Chicago's Democratic Party. In the process, he manages to throw in as many spurious ad hominem attacks on Obama as he can, calling him a "friend of race-baiters" and a "man who would lead our efforts against terrorism yet was friendly with Bill Ayers, the unrepentant 1960s terrorist."

When Blumenthal worked in the White House, a big thorn in Bill Clinton's side was the Weekly Standard, the right-wing magazine edited by William Kristol and owned by Rupert Murdoch. But in mid-February, Blumenthal's email attack featured an article, "Republicans Root for Obama," written by Weekly Standard executive editor and Fox News talking head Fred Barnes. That same month, Blumenthal also offered up a piece by Scott McConnell, titled "Untested Savior," that appeared in The American Conservative (a magazine founded by Pat Buchanan) claiming that Obama "would probably lead them [Democrats] to disaster in November."

When Blumenthal isn't relying directly on anti-Obama smears from the extreme right, he's pumping up more traditionally sourced material, from the Washington Post, New Republic, and other publications, to question and damage Obama's character and electability. On several occasions, Blumenthal has circulated articles from the Chicago Sun Times and the Chicago Tribune about Obama's ties to developer Tony Rezko, a relationship Obama has said he regrets. In one email, Blumenthal wrote: "The record on Obama's fabled 'judgement'? So how would he conduct himself in those promised summits without preconditions with Ahmadinejad, Kim Jong Il, Chavez, Castro, and Assad? Let's look at how he did with Tony Rezko."