Quds city, Nov 10, SPA -- A fiery union leader won a stunning victory over Shimon Peres in the leadership contest for Israel's Labor Party, officials said Thursday, dealing a blow to the elder statesman that could endanger the country's shaky governing coalition. Amir Peretz has promised to pull Labor out of Prime Minister Ariel Sharon's government, raising the likelihood of early elections. The defeat also could spell the end of Peres' distinguished, six-decade political career. Peres had been heavily favored to win, according to a report of the Associated Press. Party secretary Eitan Cabel, announcing Peretz's victory, said the labor leader captured over 42 percent of the vote, while Peres took just under 40 percent. A third candidate, former party head Binyamin Ben-Eliezer, got 17 percent.