KAYAWA, Nigeria — Nigerians chose their president in an election Saturday many hoped would show how Africa's most populous nation could hold a credible vote without the violence and rigging that marred previous ones, though children cast ballots and party officials helped others press their inked fingers to paper.Despite widespread security concerns after bombs hit a vote-counting center and a polling station during last weekend's legislative elections, voting in the oil-rich country appeared orderly Saturday apart from a minor explosion in one northern town.Read More...