FWD.us, the nonprofit organization Facebook CEO Mark Zuckerberg founded, is losing some of its star support. (Josh Edelson/AFP/Getty Images)

It has been only a month since Mark Zuckerberg, Facebook’s co-founder and chief executive, pulled together an impressive roster of tech executives to advocate for immigration reform through FWD.us, a nonprofit lobbying organization.

But the group is already losing some of its star power.

Some environmental groups are complaining that FWD.us has funded television ads supporting politicians who back construction of the Keystone XL oil pipeline and proposals to drill for oil in the Arctic National Wildlife Refuge. The ads do not mention immigration reform but support politicians who may be able to help ease immigration proposals through the Senate.

Tesla and PayPal co-founder Elon Musk and Yammer chief executive David Sacks withdrew support from the group Friday.

Tesla spokeswoman Shanna Hendriks confirmed that Musk has left the group but did not elaborate on why. FWD.us confirmed that two supporters, including Musk, had left the group but did not confirm Sacks’s departure. Yammer, a social-media company owned by Microsoft, did not respond to a request for comment, but Sacks’s name has been removed from the advocacy group’s Web site.

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The ads were bankrolled by a subsidiary of FWD.us called Americans for a Conservative Direction.

Several left-leaning groups, including MoveOn.org and the Sierra Club, said last week they would no longer display ads on Facebook. Wireless carrier Credo Mobile, which advocates on liberal issues, has gone further, launching a petition Monday calling for Yahoo chief executive Marissa Mayer and LinkedIn co-founder Reid Hoffman to follow Musk and Sacks and distance themselves from the group.

“We want to ask: Is this really the kind of politics you want to be involved in?” said Becky Bond, Credo Mobile’s political director. “In the tech world, we have more a belief in transparency. It’s surprising that a bunch of tech giants who are so smart when it comes to running their businesses could be so dumb as they get involved in politics.”

Neither Yahoo nor LinkedIn responded to a request for comment on the petition.

In a statement, FWD.us spokeswoman Kate Hansen said the group recognizes “that not everyone will always agree with or be pleased by our strategy — and we’re grateful for the continued support of our dedicated founders and major contributors. FWD.us remains totally committed to supporting a bipartisan policy agenda that will boost the knowledge economy, including comprehensive immigration reform.”

The group’s other supporters include Google’s executive chairman, Eric Schmidt; Microsoft chairman and co-founder Bill Gates; and Napster co-founder and founding Facebook president Sean Parker.

While several members of Facebook’s staff, including chief operating officer Sheryl Sandberg, have extensive experience inside the Beltway, Zuckerberg’s decision to found the group marked his first major foray into political advocacy.

In a Washington Post op-ed announcing FWD.us, Zuckerberg called current U.S. immigration policy “unfit for today’s world.”

FWD.us would like the government to increase the number of short-term visas, known as H1Bs, it issues every year, potentially making it easier for the tech industry to hire foreign-born computer engineers. In his op-ed, Zuckerberg said the group wouldstrongly support those willing to take the tough stands necessary to promote these policies in Washington.”

Facebook declined to comment for this article.

(The Washington Post Co.’s chairman and chief executive, Donald E. Graham, is a member of Facebook’s board of directors.)

Related stories:

Liberal groups boycotting Facebook over immigration push

Why Mark Zuckerberg cares about immigration reform

Facebook flexes political muscle with provision in immigration bill

Zuckerberg Op-ed: Immigration and the knowledge economy

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