Union spokesman Tom Geiger said 98 percent of those who cast ballots over the past week endorsed a strike if they can't get an acceptable contract.
Whether the checkers, baggers, meat cutters and other employees of Safeway, Fred Meyer, QFC and Albertsons stores will soon walk off the job remains to be seen.
"We hope the employers come to their senses and make a fair proposal that respects me and my co-workers and our families," said Jessica Roach, a Fred Meyer worker, in a news release issued following the announcement of the results in Seattle. "But if they force us to strike, we are ready."
Employees represented by the United Food and Commercial Workers regional locals 21 and 367 and by Teamsters Local 38 based in Everett have been in contract negotiations since March with representatives of the four major grocers.
The current contract expired in May for roughly 20,000 workers but has been extended indefinitely. Of those, 2,127 are in Snohomish County.
The authorization vote doesn't mean there will be a strike. Under terms of the contract, the union must give an employer 72-hour notice before workers can walk out.
Similarly, the employers must provide the unions 72-hour notice if they intend to lock out workers.
Union officials say the companies are seeking to stop providing health care coverage for employees working less than 30 hours a week and reduce pay for those who work on holidays. The companies are not offering an increase in hourly wages either, they said.
The lead negotiator for the companies declined to discuss specific issues in the negotiations.
Scott Powers, vice president of Allied Employers in Kirkland, said he did not think there would be a walkout but that the companies are preparing for one, should it occur.
The last grocery strike in the region was in 1989 and lasted nearly three months.
Jerry Cornfield: 360-352-8623; firstname.lastname@example.org.