The two parties had earlier scuttled preparations ahead of the October 19 vote, which was blocked by police at the eleventh hour.
Former President Mohamed Nasheed's Maldivian Democratic Party (MDP) has endorsed the second round lists.
In today's voting, 46-year-old Nasheed's main challenger is Abdulla Yameen of PPM, the half-brother of Maumoon Abdul Gayoom, who was President from 1978 to 2008.
The third candidate is business and resort tycoon Qasim Ibrahim of the JP.
