By Nick Carey and Timothy Mclaughlin CHICAGO - Jubilant fans of the Chicago Cubs erupted in celebration on Saturday when the franchise clinched a berth in this year's World Series, pumped up by the dizzying prospect that their team could win Major League Baseball's top prize for the first time since 1908. Chicago's North Side turned into a roving street party as thousands of people wearing "Cubbie" blue spilled out of Wrigley Field after witnessing the team vanquish the Los Angeles Dodgers 5-0, giving the Cubs the National League championship for the first time in more than 70 years. Long known as "lovable losers," the Cubs now have their sights set on an even more elusive prize: winning the franchise's first World Series title in more than a century and ending the longest drought of its kind in professional sports.