Two of the tech entrepreneur’s pet political causes are working at cross-purposes, threatening to undermine Parker’s bid to become a Beltway ambassador of young Silicon Valley. The projects — immigration and campaign finance reform — have nothing to with each other substantively. But the former Facebook president’s $500,000 contribution to the Mayday PAC, a super PAC promoting candidates who want to get big money out of politics, is helping fund an attack on Rep. Fred Upton (R-Mich.), a moderate organizing support for an immigration overhaul in hostile territory amid House Republican ranks.

And Parker’s not alone. LinkedIn co-founder Reid Hoffman and venture capitalist Fred Wilson likewise are major supporters of FWD.us, the Mark Zuckerberg-initiated push to gather tech industry support for an immigration overhaul…while also cutting six-figure checks to the Mayday PAC. The investments in the two groups would have passed without incident. But earlier this month, Mayday, founded by Harvard Law school professor Lawrence Lessig, announced plans to spend big against Upton, a low-key, 14-term incumbent wielding considerable power over the tech industry and others as chairman of the House Energy and Commerce Committee.

On October 9, Mayday announced it was going after Upton for being the “worst of the worst,” exemplifying “money’s corrupting influence in politics,” and it has since dumped nearly $1.5 million into negative ads in the lawmaker’s southwestern Michigan home base. That’s been enough to put a serious scare into Upton, who won his last election with 55 percent of the vote in a swing district that Obama carried in 2008 and lost, narrowly, to Romney in 2012. Last Friday, Upton told the Kalamazoo Gazette editorial board that he’s tracked down Mayday donors. “I do know some of the folks that funded the PAC, and as I’ve talked to them, as I have, they are under — they were under the illusion that this was a group that was trying to focus on dysfunction, taking it out, getting people that can work together,” Upton said. “And the people that I have talked to, some of them have put six figures into this PAC, they are really ashamed. They are distraught. They said they were taken for a ride. It’s too late. They bought the stuff.”

Blowback over the anti-Upton campaign has been percolating among Washington tech lobbyists for weeks, bursting into the open on Monday, when the Huffington Post reported that Upton and a top aide placed “angry calls” to Mayday donors. Upton and Parker declined to comment for this story, but sources close to the situation confirmed that the two have talked about the Mayday attack. Wilson and Hoffman also declined to comment. But among the execs giving to both groups, Parker has done the most recently to raise his political profile. Just yesterday, Fortune posted a story about how Parker’s activism is stirring controversy in his own hometown. The billionaire is supporting a ballot initiative to make life easier for those with cars in San Francisco — a bid, he says, to help the working poor, though local environmental groups and editorial boards are blasting it as backwards. Parker did comment for that story. And in it he explained the strategy behind his national giving, which he’s broadened from exclusively Democratic to now supporting moderate Republicans, as well, as a check on right-wing extremists in Congress.

In that context, it’s seems likely Parker and the others simply didn’t know where their Mayday contributions would end up. “I can’t in a million years imagine a scenario where those guys were told, ‘This is what we’re doing,’ and they said ‘Ok,” said one Republican strategist supporting immigration reform. “People make mistakes when they’re throwing money around. What I find most surprising is they’ve done nothing, and I mean nothing, to try to clean it up.”

FWD.us itself has made its share of missteps since launching last year by treading into hot-button debates unrelated to immigration reform. Last spring, the organization bankrolled ads for lawmakers supporting construction of the Keystone XL pipeline, a cause anathema to many of its own environmentally inclined founders. Tesla CEO Elon Musk and Yammer CEO David Sacks quit in protest. Last month, after a Congress that opened with what appeared to be major momentum for an immigration overhaul packed up for the campaign trail with the debate still mired in the House, Zuckerberg ousted FWD.us president Joe Green, his former Harvard roommate.

Parker, meanwhile, is pushing into politics with his latest startup, as well. Brigade — based on a company called Causes that he launched with Green back in 2007 — is aiming to serve as a “civic network” in the way that Facebook is a social one. The idea is to build a platform that will reverse the decades-long slide in civic engagement, and a beta version is expected to go live in January. As Parker is learning first-hand, the whole civic engagement thing is tougher than it looks.