Strategic voting could once again drive supporters away from the NDP and into the waiting arms of Paul Martin's Liberals, indicates a new opinion survey that comes as the federal election campaign enters its crucial second half. Stakes are high as polling suggests Mr. Martin and Conservative Leader Stephen Harper are in a statistical dead heat, leading observers to warn an ugly fight for dominance lies just ahead. And that means NDP supporters who fear a Conservative win could become crucial in the Jan. 23 vote as some consider shifting alliances to tip the balance in the Liberals' favour, says...