BART’s hopes of having its new Warm Springs extension opened before voters decide on the system’s mega-$3.5 billion rehab bond are slipping away fast.

Transit system brass had initially planned on holding opening ceremonies this weekend — a photo op that would have been just in time for the Nov. 8 election, when BART is asking voters to approve Measure RR.

“What I’m told is that they are achingly close, which is why they were looking at opening it this weekend, but they are not 100 percent certain that it would be reliable for opening,” said BART board President Tom Radulovich.

It’s not that there are significant problems with the 5.4-mile extension south from the Fremont Station, we’re told. BART just wasn’t able to finish testing all the various components in time.

“It would definitely be worse if something went wrong, so (delaying the opening) made sense,” Radulovich said.

“We still plan to have the station open this fall,” said BART spokeswoman Alicia Trost. But no date has been set.

BART orginally expected to have the Warm Springs extension open in 2014, before various delays pushed the planned opening to this past summer. Then the need for electrical and technology upgrades pushed the ribbon-cutting into the fall.

There may have been a touch of election season politics at play as well.

The BART bond measure, which would fund improvements to electrical and train-control systems, rails and stations, needs a cumulative two-thirds majority approval in San Francisco, Alameda and Contra Costa counties. Measure RR is polling well in communities along BART lines, but support falls off in areas that are farther from stations.

Opening the Warm Springs extension before the election would give voters in southern Alameda County added reason to vote for the bond. The opening also would show the rest of the Bay Area that BART is able to deliver on big projects.

“For me, the message would have been mixed,” Radulovich said. “On one hand, we don’t want to send out the message that this bond is for extensions — it’s for upgrading the core system. On the other, it would have shown we can deliver on a big project, and that would have been to our credit.”

Fair or foul: A complaint filed with state watchdogs has put the spotlight on a new big-dollar player in San Francisco politics — a nonprofit housing group that refinanced its federally subsidized apartments for millions of dollars, then pumped $270,000 of the extra cash into progressive campaign causes.

“It’s shocking — they are stealing taxpayers’ money that should be going into affordable housing and rent subsidies, (and) not for politics,” said Sonja Trauss, founder of the development-friendly SF Bay Area Renters Federation.

Not so, says John Elberling, head of the Todco nonprofit housing group. “I see it as David versus the Goliaths of City Hall and their multimillion-dollar fat-cat funders,” he said.

Whatever the case, many see the behind-the-scenes play as a game changer for several progressive-backed measures on the San Francisco ballot.

Todco and its partners have built and operate eight complexes in the South of Market area with 956 units for low-income and elderly tenants. Many of the apartments were built in the 1980s and have since been paid off.

“A couple of years ago, we refinanced and renovated them and came out several million dollars ahead,” Elberling said.

“That is a big surplus that we didn’t need for regular expenses, so we funded our ... Yerba Buena Neighborhood Consortium to do community advocacy,” he said.

As part of the arrangement, Todco set aside $300,000 a year to fund litigation and political causes.

This year, the group has spent $149,000 in support of Measure X, which aims to preserve arts and design space in the South of Market. The measure was sponsored by Supervisor Jane Kim, who of course is also running for state Senate.

At least $83,000 more has gone to committees supporting four other measures.

They are Proposition M, Supervisor Aaron Peskin’s proposal to create an oversight commission on affordable housing spending; Proposition H, to create a public advocate office; Proposition D, to require special elections to replace supervisors who leave office early, rather than having the mayor appoint them; and Proposition L, to give the Board of Supervisors appointments to the Municipal Transportation Agency. The members of that panel are now named by the mayor.

All the propositions are opposed by Mayor Ed Lee and his allies — who have spent $1.3 million and counting to defeat them.

Tony Winnicker, a Lee aide who is on leave to run a campaign committee working to defeat the measures, called Todco’s strategy “a campaign finance shell game where the original source of money is the taxpayer.”

Elberling said that’s nonsense. “Thirty years ago, it was federal and state funds, and a little bit of city money, but all of that has been repaid,” he said.

Trauss, the renters federation head, filed her complaint with the state Fair Political Practices Commission in September. The agency has since opened an investigation.

The commission doesn’t comment on ongoing investigations, but Elberling appears confident that what his group did is all legal.

Still, he understands why the other side is upset.

“We’ve got a lot of pebbles now to shoot at the Goliaths,” he said. “And I’m a pretty good shot.”

S an Francisco Chronicle columnists Phillip Matier and Andrew Ross appear Sundays, Mondays and Wednesdays. Matier can be seen on the KPIX TV morning and evening news. He can also be heard on KCBS radio Monday through Friday at 7:50 a.m. and 5:50 p.m. Got a tip? Call (415) 777-8815, or email matierandross@ sfchronicle.com. Twitter: @matierandross