Mexico’s governing Morena party looked poised to dominate the Supreme Court on Tuesday, moving closer to controlling the third branch of government, according to early results in the country’s divisive, first-ever election to overhaul the courts at every level.

At a news conference, the leader of the country’s electoral authority, Guadalupe Taddei, said that over 90 percent of votes for court justices had been counted, and named the nine likely winners.

In a sign of Morena’s apparent success, the five women and four men projected to sit on the new Supreme Court were endorsed on lists distributed by Morena operatives and supporters.

The nationwide elections on Sunday transformed the judiciary from an appointment-based system to one in which voters choose judges and magistrates — a hugely ambitious, far-reaching experiment by a large democracy. Morena leaders who pushed the overhaul into effect argue it will help root out corrupt officials, democratize the judiciary and begin to repair a justice system that most Mexicans see as unresponsive and broken.

But opposition figures and legal experts criticized the plan, saying it discarded the career requirements of the old system and kept the door open for criminal groups to influence judges.

Critics also argued that the reform could give Morena control over the judiciary, undermining the system of checks and balances.