The bad blood between some of the country’s most well known Tea Party organizations was unmistakably on display by two prominent activists from rival groups Monday.

“The man is a disgusting, vile, racist, pig…I don’t stand with people like that,” said Tea Party Patriots national coordinator Mark Meckler, when asked about Mark Williams of the Tea Party Express.

But Meckler’s disgust, coming on the heels of Williams being harshly criticized for writing racially insensitive material on his blog about the NAACP, is not just personal.

“It’s a fake,” he said of the Tea Party Express’ organization. “They’re fake. They’re part of the Republican establishment.”

And Williams isn’t a big fan of Meckler either.

“I loved the guy until I found out that he was an opportunist out looking to cash in on sincere peoples’ fears about their nation,” Williams told The Daily Caller by e-mail. “He loved me until he realized that I knew what he is.”

There are hundreds, if not thousands, of local conservative grassroots groups out there. But of the largest national Tea Party groups who are most often mentioned in the media — the Tea Party Express, the Tea Party Patriots, the Tea Party Nation and the Tea Party Federation — the bad blood is flowing.

So who are these groups and what’s the root of their discontent with each other?

—    The Tea Party Express is known for their bus tours across the country, and their ardent endorsements of candidates like Sharron Angle in Nevada. As for Angle, they helped transform her from a long-shot candidate in the Senate race to the GOP nominee. Founder Joe Wierzbicki says they have over 400,000 members who’ve signed up with them. But their critics claim that despite the organization’s name, the Tea Party Express is not grassroots at all. Founded by Republican strategists Wierzbicki and Sal Russo, memos from the early days of the movement portray the group conveniently latching onto the Tea Party name to help raise money for their Republican political action committee. And local activists have spoken out against their endorsements, saying they’re stepping on the toes of local Tea Party voters.

—    The Tea Party Patriots, led by national coordinators Meckler and Jenny Beth Martin, has 2,300 local chapters under their banner. “We do what our members tell us what to do,” Meckler says. “We don’t speak for them.” Yet other Tea Party activists scoff at the Tea Party Patriots’ perceived haughtiness and unwillingness to work with other groups. The Tea Party Patriots, their critics say, project a sense of ownership over the movement and think they alone represent the real Tea Party.

—   The Tea Party Federation formed during the days of the health care vote on Capitol Hill to offer unified, rapid response to racial accusations. The federation was founded by a number of activists and its broad membership of groups include Dick Armey’s FreedomWorks, The Memphis TEA Party and New York’s TeaParty365. Several critics say the group is trying to assert itself as a leader of the leaderless movement by making statements on behalf of all Tea Partiers, when they don’t have the right to do so.

—    The Tea Party Nation made headlines earlier this year by hosting the first National Tea Party Convention, headlined by Sarah Palin, in Nashville. A number of groups — like Tea Party Express and Tea Party Patriots — did not participate, especially after reports that Judson Phillips, a relatively unknown Tennessee lawyer who leads the group, was trying to make money off activists. Critics pointed to the high-ticket price of the event. Phillips was unapologetic about how he hoped to turn a profit.

When it comes to discussing these national groups, the buzz-word among activists is “ego.” Activist Robin Stublen, during an interview in May, said Williams and Meckler’s dislike for each other is “an ego thing.”

“Williams has an ego, Meckler has an ego,” Stublen said then.

When the Tea Party Federation expelled Williams this weekend because of his blog post, Williams blamed the “stronger egos and personalities” of the Tea Party Federation — who see Tea Party Express as competition — for going after him.

Phillips of Tea Party Nation put the rivalries of all the groups this way: “In some instances you have egos playing against each other, in some instances you just have simply different points of view.”

Christina Botteri of the Tea Party Federation called some of the infighting amongst the groups “territorial.” But she refused to speak negatively of the Tea Party Patriots, when asked about Meckler’s criticism that the group is not grassroots: “I’m not interested in getting into it with the Patriots. …To this day, they’re probably one of the best sources of groups in the movement.”

But her group called Williams’ blog post that led to his expulsion from the Tea Party Federation “clearly offensive.” Wierzbicki responded by saying, “Most rank-and-file tea party activists think we’re talking about Star Trek when we try to explain who the ‘Federation’ is.”

Phillips’ Tea Party Nation was a member of the Tea Party Federation, but not for long. “We had a difference in opinion on how things work,” Phillips said. As for the Tea Party Patriots, Phillips said he’s tried to contact them about being involved in October’s second Tea Party Convention in Las Vegas, but haven’t had much luck. “They really don’t work with other groups,” he said.

But Phillips refused to elaborate on those groups. “One of the things that people like about Tea Party Nation is we don’t like to trash other groups,” he said.

But neither Williams nor Meckler — who in requests for comment in the past have refused to speak on-the-record very much about their issues with other organizations — had a problem doing so Monday.

Williams, in an email, forwarded a link to an archive of stories about Meckler receiving GOP money for political work. Meckler, who practiced law in California before devoting much of his time to the organization, denies Williams’ claim that he’s personally profiting from his activism.

“I’ve spent my entire life-savings doing this movement. If I was out to make a buck, I would’ve stayed as a lawyer,” he said.

Meckler says he hopes the Tea Party Express becomes a “footnote in the Tea Party movement,” considering they allowed Williams to chair the organization despite a long-history of being accused of making racial remarks.

“Anybody who claims that they didn’t know what Mark Williams was about, maybe they don’t have a computer. Maybe they don’t know how to use Google,” he said.

Sometimes it appears the groups are working against each other, even though they share similar political goals. During the health care debate, The Daily Caller reported that some members of the Tea Party Patriots had discouraged activists from attending a Tea Party Express rally. The Tea Party Patriots have denied the charge, but the Tea Party Express said it was true.

Said Tea Party Express spokesman Levi Russell then: “There is some truth to that, sadly.”

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