Elizabeth Warren seeks spark in final sprint to Iowa

STEVE PEOPLES, SARA BURNETT and WILL WEISSERT Associated Press DES MOINES, Iowa (AP) — Elizabeth Warren is fighting to regain momentum in the turbulent fight for the Democratic presidential nomination amid lingering questions about her authenticity and electability. Warren was considered a leader in the crowded race through the fall, yet just seven days before Iowa's first-in-the-nation caucuses, allies, adversaries and new polling suggest that progressive rival Bernie Sanders has a slight advantage — at least in the battle for the party's left wing. That's just as establishment-minded Democrats begin to rally behind former Vice President Joe Biden, who has tried to stoke fears about his more liberal rivals' ability to defeat Trump this fall. Warren's uncertain status raises quest