Populist Conservative budget puts Canada's Liberals in election squeeze

By Leah Schnurr and Randall Palmer OTTAWA (Reuters) - Canadian Prime Minister Stephen Harper, facing a battle to win reelection to a rare fourth term in October, has boosted his chances with a populist budget expected to energize his base. The tax breaks in the budget the Conservative government delivered on Tuesday, plus the cold hard cash it will give to every family with children starting in July, put pressure on Harper's main opponent, Liberal leader Justin Trudeau, to spell out an econ