A campaign waged by the Screen Actors Guild to persuade members of a smaller rival union to vote down a new contract has foundered, an outcome that could weaken SAG’s leverage in negotiations with the Hollywood studios.

Members of the American Federation of Television and Radio Artists on Tuesday approved a new three-year prime-time TV contract, dealing a blow to SAG leaders who had gambled heavily on defeating a contract they blasted as bad for actors.

The vote – widely viewed as a barometer of support for SAG negotiators – doesn’t eliminate the prospect of a strike, but it leaves the guild with fewer alternatives. The protracted negotiations are causing widespread uncertainty throughout Hollywood, holding up feature film productions and casting a pall over the upcoming fall TV season.

“It’s hard to not see this as a setback because they invested so much in this and drew a line in the sand,” said David Smith, a labor economist at Pepperdine University. “It’s probably going to limit their ability to negotiate for what they want.”

SAG leaders could still seek a strike authorization vote from members, but that option is considered risky given the deteriorating economy and strike fatigue after the 100-day writers walkout that ended in February.

“The town has been fairly terrorized this year and actors don’t have more guts than the average person,” former SAG President Ed Asner said during a meeting with TV critics on Tuesday. “They realize the tremendous cost. Probably, if push came to shove, most would vote against it. I myself would vote for it, but I would be in the minority as I usually am.”

Not surprisingly, the clashing unions interpreted the vote by AFTRA members differently.

SAG declared a moral victory, noting that the 62.4% ratification vote was below the norm, given that labor contracts are typically approved by more than 90% of voting members. SAG also argued that results were skewed by the non-actors who voted, citing an AFTRA flier that urged broadcasters to endorse the contract even “if you haven’t worked under this contract.”

AFTRA leaders countered that broadcasters account for less than 10% of the union’s 70,000 members, 52,000 of whom are actors. AFTRA did not report how many of its members voted. SAG, which unlike AFTRA also represents film actors, has 120,000 members.

AFTRA President Roberta Reardon praised actors for displaying “courage in the face of potential retribution by taking a stand against disunity.” She proposed various conciliatory steps with SAG, including organizing a meeting to revisit the possibility of merging the two unions.

The contract ratified Tuesday was modeled after similar pacts negotiated by directors and writers. Although the accord includes pay hikes for actors and establishes payments for programs streamed online, SAG contended it didn’t meet such key bargaining goals as increasing residuals from DVD sales, and ensuring that all Internet programs were covered by its contract.

SAG allocated as much as $150,000 toward persuading 44,000 joint members to reject the federation’s contract, blanketing members with ads, e-mails and automated phone calls. AFTRA countered by raising fears that voting down the contract would heighten the prospects of a strike.

The campaign deeply divided the ranks of actors and has been a major distraction in SAG’s negotiations with the studios. The opposing camps failed to reach agreement on a new contract to replace the one that expired June 30.

Talks will resume Thursday, when SAG is expected to respond to the studios’ final offer, which was similar to the pact offered to AFTRA and included more than $250 million in gains above the existing contract, the studios said.

If, as expected, SAG rejects the final offer, the studios could declare an “impasse,” enabling them to legally enforce their final proposed contract. The studios also could impose a so-called lockout, which would block actors from working and trigger what would amount to a strike. That, however, is viewed as a draconian measure because it would shut down most production, which would cost the studios dearly – in addition to possibly creating sympathy for actors.

 richard.verrier@latimes.com

 claudia.eller@latimes.com

Times staff writer Maria Elena Fernandez contributed to this report.