Workers represented by the United Auto Workers union ratified a four-year contract with Chrysler Group LLC, the last Detroit automaker to reach a labor deal.

About 55 percent of hourly workers at Chrysler voted in favor of the agreement, the UAW said on Wednesday.

But in a rare twist, nearly 56 percent of skilled-trades workers, which make up a small portion of Chrysler's 26,000 UAW-represented workers, rejected the contract.

It's not everything our members deserve, but we did the best we could in these uncertain times and negotiated an agreement that will ensure Chrysler's viability so that we can share in its economic success once it has regained financial stability. said UAW Vice President General Holiefield in a statement.

The terms of the Chrysler contract are far less generous than the deals reached earlier at General Motors Co (GM.N) and Ford Motor Co (F.N). At both Ford and GM, the contracts were approved by nearly 2-to-1 margins.

Chrysler workers are guaranteed a signing bonus of $1,750 upon ratification, less than the $5,000 to be given at GM and the $6,000 signing bonus offered to Ford workers.

The ratification of the Chrysler deal now paves the way for the UAW to focus on organizing U.S. plants operated by foreign automakers.