BEIRUT—Lebanese businessman Najib Mikati secured enough votes in parliamentary consultations on Monday to be designated the next prime minister, and now faces the difficult challenge of forming a viable government to tackle a financial crisis. Mikati has been prime minister twice before and, unlike many Lebanese leaders, does not represent a political bloc or hail from a dynasty. He received 72 votes out of a total of 118 members of parliament. Like previous nominee Saad al-Hariri, he must navigate the sectarian, power-sharing structure and secure agreement on a cabinet equipped to address the financial meltdown in Lebanon, one of the world’s most heavily indebted states. “I don’t have a magic wand and I can’t work miracles,” Mikati said after his nomination, but added that he had been studying the situation and had “the necessary international guarantees.” Mikati is the third person to be nominated since Hassan Diab’s government resigned after …