JERUSALEM—Uncertainty hovered over the outcome of Israel’s parliamentary election Wednesday, with both Prime Minister Benjamin Netanyahu and sworn political rivals determined to depose him apparently lacking a clear path to a governing coalition. Deadlock in the 120-seat parliament was a real possibility a day after the election, which had been dominated by Netanyahu’s polarizing leadership. With about 90 percent of the vote counted by Wednesday morning, Netanyahu’s Likud party and its ultra-Orthodox and far-right allies fell short of a 61-seat majority—even if the Yamina party of Netanyahu ally-turned-critic Naftali Bennett were to join a Netanyahu-led government. Bennett has refused to endorse either side. At the same time, a small Arab party emerged as a potential kingmaker on Wednesday morning after the latest count indicated it would cross the threshold to get into parliament. Like Bennett, the head of the Ra’am party, Mansour Abbas, has not ruled out joining either camp. …