DUBLIN, Ireland - Sinn Fein members overwhelmingly voted Sunday to begin cooperating with the Northern Ireland police, formally abandoning their decades-old hostility to legal law and order in the British territory.

The result -- confirmed by a sea of raised hands but no formally recorded vote -- represented a stunning triumph for Sinn Fein chief Gerry Adams, the former Irish Republican Army commander who has spent 24 years edging his IRA-linked party away from terror and towards compromise. It strongly improved the chances of reviving a Catholic-Protestant administration, the long-elusive goal of the 1998 Good Friday peace pact, by Britain's deadline of March 26.