The backlash against Mark Zuckerberg's political advocacy group is gathering steam with a campaign to pick off many of its high-profile Silicon Valley backers.
Activists on Monday identified the next batch of figures they hope will defect following the departure of Elon Musk and David Sacks, adding fresh pressure to Zuckerberg's nascent Fwd.us organisation.
Musk and Sacks quit last week after accusations the Facebook founder's political lobby group, set up to push for immigration reform, had made an unholy alliance with anti-environmental politicians.
"It's time for other tech industry luminaries to make it clear where they stand. Follow Elon Musk's example and resign from Fwd.us," said Credo, the advocacy arm of Credo Mobile, in a petition which by Monday afternoon had 32,000 signatures.
It singled out LinkedIn's Reid Hoffman, eBay's John Donahoe, Yahoo's Marissa Mayer and Kleiner Perkins' John Doerr for pressure from critics of Zuckerberg's initiative.
The billionaire launched his boldest foray into politics in March, vowing to mobilise grassroots activists and tech moguls into a force to overhaul US immigration laws. Current restrictions curb Silicon Valley's ability to recruit and nurture foreign talent.
Fwd.us said it would help re-elect conservative and liberal politicians alike as long as they supported immigration reform.
The group triggered an outcry, however, by funding television advertisements touting the pro-oil views of Lindsay Graham, who champions the Keystone XL pipeline, and Mark Begich, who wants drilling in the Alaska National Wildlife Preserve.
A liberal coalition including the Sierra Club, the League of Conservation Voters and MoveOn.org announced last week it would temporarily suspend buying advertisements on Facebook, a largely symbolic protest.
Musk, who as chief executive of Tesla Motors has staked his reputation on green technology, quit Zuckerberg's group on Friday, saying immigration reform should not be pursued at the expense of other important causes.
"I have spent a lot of time fighting far larger lobbying organizations in DC, and believe that the right way to win on a cause is to argue the merits of that cause," he said. "This statement may surprise some people, but my experience is that most (not all) politicians and the staffs want to do the right thing and eventually do."
Sacks, who founded the social network Yammer, was widely reported to also have quit the organisation but has yet to make a public statement.
Credo Action, the advocacy arm of the cellphone networker Credo Mobile, urged Zuckerberg's critics to keep up the momentum with direct appeals to his remaining prominent tech allies, such as Hoffman, Donahoe, Mayer and Doerr.
"Silicon Valley stars … are sensitive to public backlash from the people who power their social networks or use their products or services. If enough of us push back and keep this issue in the public eye, they will be under immense pressure, not just from us but from their staff and shareholders, to stop supporting Fwd.us," it said.
A spokesperson for the lobby group, speaking to the New York Times last week before Musk's announcement, brushed off criticism. "We recognize that not everyone will always agree with or be pleased by our strategy. Fwd.us remains totally committed to support a bipartisan policy agenda that will boost the knowledge economy, including comprehensive immigration reform."
Supporters point out that Bill Gates and other heavyweights remain on board and that the lobbying reflects Silicon Valley's can-do, goal-oriented ethos.
The Fwd.us site has ignored the controversy, and Zuckerberg has declined to comment.
TechCrunch fuelled the perception of a beleaguered enterprise with an article analysing why it had become reviled even by some of its own members.
"There's a reason most lobbies don't bother with grassroots activism: communities don't get excited about the kinds of soul-crushing moral compromise necessary in DC politics. So, when Fwd.us rolled up with millions in hand claiming to be the voice of the technologists, those who felt misrepresented freaked out. Even more confusing, when confronted, Fwd.us chose to do something no other major organization in technology has done: it remained silent."
The article noted that Twitter co-founder Evan Williams tweeted a link to a scathing blog post from Branch CEO Josh Miller.
"In service of noble causes, Fwd.us is employing questionable lobbying techniques, misleading supporters, and not being transparent about the underlying values and long-term intentions of the organization. More discouragingly, the leaders of the technology industry (and of Fwd.us) have built their careers on bringing meaningful change to the world. They should be doing the same in Washington."