SANTA FE, N.M. (AP) — The Republican Party says its election poll challengers in New Mexico are unfairly being denied oversight of the initial verification process for absentee ballots, in a lawsuit filed Monday with the state Supreme Court.

The lawsuit from the GOP and several allied state legislators and county clerks alleges that independent oversight is not being allowed in some counties as election officials verify signatures and partial social security numbers on the outside of absentee ballot envelopes. It also says the response to rejected ballots is being left open to interpretation.

Election “challengers” are appointed by political parties including the GOP at individual polling locations to view voting machines, rosters and the work of precinct boards as ballots are processed and tallied.

The Republican Party said in a news release that multiple counties have denied Republican poll challengers the ability to perform their duties by “taking absentee ballots behind closed doors and out of sight.”

Alex Curtas, a spokesman for the New Mexico secretary of state's office, said election regulators are complying with a robust oversight process and criticized the timing of the lawsuit as worrisome so close to Election Day.

“To have the Republican Party declare that duly elected county clerks are purposefully deceiving the public is a worrying tactic ahead of a highly-charged election,” Curtas said. “Our office is confident that the absentee ballot processing procedures being followed ... and voters should have confidence that their vote will be counted and that their personally identifying information will be protected.”

The lawsuit hinges on temporary election procedures adopted by lawmakers in June in response to the coronavirus pandemic.

Under the law, absentee voters must sign and place the last four digits of their social security number on the outer envelop — concealed by a so-called privacy flap. For rejected ballots, clerks must send a notification to voters within one day.

The lawsuit alleges that partisan challengers are being shut out of the initial verification process unnecessarily, based on privacy regulations, and should be allowed to take their own steps to notify voters about rejected ballots.

The Supreme Court ordered the secretary of state to respond quickly to the lawsuit. Democratic-appointed Justices Shannon Bacon and David Thomson have recused themselves as they run for election.

More than 250,000 absentee ballots have been cast statewide as of Monday, among 560,000 total votes so far, according to statistics from the secretary of state's office. In 2016, about 804,000 people voted as Hillary Clinton won the state and Democrats swept statewide and congressional contests.

Candidates are competing in open races for one U.S. Senate seat and the 3rd Congressional District, as Democratic Sen. Tom Udall retires and allied U.S. Rep. Ben Ray Luján runs for Senate. Republican former state legislator Yvette Herrell is challenging first-term U.S. Rep. Xochitl Torres Small in a swing-district rematch in southern New Mexico.

Plaintiffs to the lawsuit include county clerks from Lea, Chaves, Catron and Lincoln counties, as well as the Republican state House and Senate majority leaders.