MADRID — Catalonia’s three-year drive for independence was thrown into turmoil on Thursday when Catalan lawmakers voted against reinstating Artur Mas — the politician who has led the push to secede from Spain — as head of the regional government.

The vote, 73 to 62, was the second time this week that Mr. Mas had failed to persuade lawmakers to back his leadership, which has been troubled by corruption scandals, and it revealed deep divisions within the separatist movement.

His thwarted re-election now further complicates the independence drive just a day after Spain’s Constitutional Court suspended a Catalan parliamentary resolution passed on Monday that called for Catalonia to set up its own institutions as an independent republic.

Mr. Mas and other separatist leaders still have two months to overcome their differences and agree on who should lead their government and the drive toward independence. But if no deal can be reached before Jan. 10, then new regional elections will have to be held.