Benjamin Netanyahu, Israel’s conservative prime minister for the past decade, and his chief rival, Benny Gantz, a centrist former military chief, emerged neck and neck from a tight race in Tuesday’s parliamentary election, according to preliminary results. But by early Wednesday, with most of the votes counted, Mr. Netanyahu appeared poised to win a fourth consecutive term in office, and a fifth overall. A count of the broader blocs needed to form a coalition government gave Mr. Netanyahu’s Likud party a clear advantage over Mr. Gantz’s Blue and White.