CBS news writers, graphic artists and other staffers who work for the network's television and radio news operations voted by a wide margin to authorize a strike against their employer, the Writers Guild of America announced Monday.

Of the 300 employees who cast ballots in last week's special election, 81% backed a labor stoppage to protest working for more than 2 1/2 years without a contract.

The strike authorization means the WGA East and WGA West could call for a walkout at any time, although a strike is not inevitable. Union officials hope that the vote -- coming in the midst of a strike involving television and film writers who work under a separate contract -- will prod CBS back to the negotiating table. The two sides last met in January.

"It's a very powerful vote," said Michael Winship, president of the WGA East. "It proves that the CBS News folks have reached a point where they have taken this situation in their own hands and recognized that they need to get a contract, whatever needs to be done."

The union's CBS negotiating committee will meet after Thanksgiving to determine the next course of action, Winship said.

In a statement, CBS showed no inclination to compromise.

"The offer we presented nearly a year ago was fair and reasonable, and remains on the table," the network said. "It not only includes one of the best medical plans in the country with minimal employee contributions, but fair salary increases to all WGA employees as well."

"We hope there is no strike," the statement continued. "Should there be, however, CBS News, CBS Television Stations and CBS Radio remain fully prepared and ready to continue producing the highest-quality news programming for our viewers."

The labor dispute involves more than 500 news writers, editors, desk assistants, production assistants, graphic artists, promotion writers and researchers who work for CBS in New York, Washington, Chicago and Los Angeles. About 60% are at local television and radio stations; the rest are at the network.

The most recent contract between CBS and its WGA news employees expired April 1, 2005. Negotiations have been at a standstill since November 2006, when 99% of the employees voted to reject the network's last offer.

Guild officials call the contract put forth by CBS unacceptable because it would mandate lower wage increases for local radio employees than for television and network radio staffers. Another major point of contention: It would allow CBS to combine union and nonunion newsrooms, a move that could threaten the union's presence.

Noting that its members last received a pay increase in April 2004, the WGA is seeking a 3% raise for all the employees for the length of the contract, including retroactive pay since its last deal expired.

For its part, CBS said it was offering a 3% raise for television and network radio employees and a 2% hike for local radio employees. The wage increases would not be retroactive.

In a letter distributed last week to WGA East members, the network urged employees not to vote for the strike and to consider "the uncertainty of a strike in determining what is best for you and your families," according to the Hollywood Reporter.

If a labor stoppage were to occur, all-news radio stations such as Los Angeles' KNX-AM (1070), Chicago's WBBM-AM and New York's WCBS-AM probably would be the hardest hit because they would lose the staff that writes their news and headlines.

"CBS Evening News With Katie Couric," which has three news writers and several graphic artists who work under the WGA contract, would also be affected. Couric does not belong to the WGA, but she is a member of the American Federation of Television and Radio Artists.

Various unions -- including the WGA, AFTRA and the National Assn. of Broadcast Employees and Technicians -- represent different parts of the TV news business, which also employs many nonunion staffers.

In the current Hollywood writers walkout, AFTRA has instructed its members not to do the work that is usually done by members of the WGA.

If CBS news employees strike, Couric could continue editing her own copy, as she does currently, but she would not be able to write more of the nightly broadcast. Much of the additional work would fall to the program's executive producer, Rick Kaplan, and his senior staff.

matea.gold@latimes.com