State Republican Party Chairman Keith Downey said Friday that a DFL lawsuit to block Donald Trump from Minnesota's presidential ballot is "a blatant and frivolous attempt to disenfranchise" voters, while the secretary of state warned the state Supreme Court it must move very quickly to settle the matter.

DFL Party Chair Ken Martin filed a petition with the state's high court a day earlier seeking to remove Trump and his running mate, Indiana Gov. Mike Pence, on a legal technicality. The petition takes issue with the method by which Republicans selected alternate presidential electors.

The matter is of some urgency: Early voting in Minnesota starts on Sept. 23. In a court filing Friday, Secretary of State Steve Simon wrote that the Supreme Court must decide by Monday whether or not Trump and Pence are eligible for the ballot.

In a separate affidavit, a legal adviser in Simon's office said Minnesota counties already have printed about a million general election ballots.

The DFL petition says that Simon, a DFLer, erred when he accepted the state GOP's "certificate of nomination" for the Trump-Pence ticket.

A spokesman said Simon would not publicly comment on the lawsuit.

In a brief order posted Friday morning, Chief Justice Lorie Skjerven Gildea told the DFL to explain why it waited to file its suit, hinting that it could be dismissed for that reason. The GOP's filing blunder came to light more than a week ago.

In response, the DFL said it prepared its petition as quickly as possible and argued that it would be wrong to dismiss the challenge because of timing.

"The matter before the court is of national significance and no party would suffer such substantial prejudice that the Court should resolve the case on procedural grounds rather than merits," read the response from the DFL's lawyers.

Even if the DFL's petition were ultimately unsuccessful, it could force the state Republican Party to redirect vital financial resources with the election just weeks off. Several of the DFL's attorneys in the case had represented U.S. Sen. Al Franken in his successful 2008 Senate election lawsuit.

Downey's response came via news release. He said the state GOP "completed its requirements, in compliance with state law and party rules ... the ballot filing was certified by the Secretary of State and properly placed on the ballot."

Downey said Trump "got on the ballot fair and square" and accused the DFL of trying to "rig the election." Downey did not return a call seeking further comment.

At their state convention last spring, Minnesota Republicans neglected to select 10 alternate presidential electors, an obscure step but a required one in the process of electing the next president. The GOP's Executive Committee met in August to address the error and choose the alternates, but state law holds that selection must come at the state convention.

"This language is clear and unequivocal," the DFL petition read.

Martin was not granting interviews Friday. He said in his own statement Thursday night that "it is incumbent upon political parties to follow the rules binding our elections."

David Schultz, an election law expert at Hamline University, said he thinks it is highly unlikely the Supreme Court would strike Trump from Minnesota's ballot. Schultz said the state law at issue is arguably unconstitutional.

"One could easily argue this law overreaches in telling political parties how to conduct internal affairs," Schultz said. He also said Minnesota's high court has a history of election-related decisions that preserve voters' choices, rather than limiting them.

Trump's state chief moves

Also Friday, Trump's Minnesota campaign said that Mike Lukach, hired just last month as the Republican candidate's Minnesota state director, has been reassigned to Colorado.

Spokesman Andy Post said the transfer was already in the works and not related to the ballot challenge. Post took over as acting state director. He issued a brief statement about the DFL's lawsuit.

"We are focused on campaigning while state Democrats are focusing on preventing Minnesotans from having a vote," Post said.

Patrick Condon • 651-925-5049