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Legal jockeying in Pennsylvania intensified Friday as Republicans asked the U.S. Supreme Court to ensure county election officials were segregating mail ballots delivered after Election Day, the latest effort by the GOP to use the courts to intervene in the vote count as former vice president Joe Biden’s advantage grew.

On Friday evening, Justice Samuel A. Alito Jr., who received the petition because he is the justice responsible for that region, approved the GOP request for now, ordering county boards to comply with state guidance to keep the late ballots separate. However, Alito did not direct election officials to stop counting the ballots, as the Republicans had also sought. He called for a response from state officials by Saturday afternoon.

Even if the high court were to ultimately side with Republicans, the impact would likely be muted: Pennsylvania officials said they are already setting aside the small number of mail ballots that have arrived since Tuesday.

But the move was part of a broader scramble in the courts by President Trump’s campaign and other Republican figures as Biden improved his lead in Pennsylvania, Georgia and Nevada.

The GOP has sought to halt or delay the ballot count in several lawsuits filed or revived this week around the country since Tuesday. According to court filings, at least 35 lawyers — including newly appointed Republican National Committee “legal challenge teams” in key states — have been drafted by the campaign to bring cases alleging voting irregularities or missteps by election officials in the wake of an election that ran largely smoothly Tuesday.

But judges have responded skeptically as Republicans struggle to provide specific evidence to support Trump’s claim of widespread voter fraud, leading them to deny or dismiss claims of irregularities or rule-breaking in Michigan, Georgia and Pennsylvania. Voting rights advocates, election administrators and Democrats have roundly criticized the lawsuits as meritless.

Since Election Day, Trump officials have made contradictory statements on vote counting, which votes to count and when to count them. (The Washington Post)

On Thursday, judges in three states rejected lawsuits filed by the Trump campaign that challenged the ballot-counting process. Friday brought additional defeat for Republicans in Michigan, as judges rejected a lawsuit from a conservative nonprofit alleging rules were broken during ballot processing and counting in Detroit, according to lawyers involved in the case. And the GOP had another setback in Nevada, where a judge denied an emergency request to intervene in the vote count in Clark County.

The GOP’s most intense focus was on Pennsylvania, where Biden pulled ahead of Trump in the vote count early Friday.

The Pennsylvania Republican Party filed a new request in the afternoon with the U.S. Supreme Court asking it to keep state officials from counting mail ballots received after Election Day, even though some election officials said they have already set aside those ballots and are not including them in their current tallies.

Under a ruling by the state Supreme Court, election officials in Pennsylvania are allowed to count ballots that were postmarked by Tuesday and arrive by 5 p.m. Friday. But Secretary of State Kathy Boockvar (D) agreed to order counties to segregate ballots received after 8 p.m. on Election Day because of pending legal challenges from Republicans.

The state GOP said Friday that an official order from the court was necessary to ensure the ballots have been segregated, but acknowledged that the party did not know of any county specifically not complying with Boockvar’s order. Party representatives contacted each of the state’s 67 counties and 42 affirmed they were segregating the ballots, while the rest did not respond, the filing stated.

In a filing to the Supreme Court late Friday, the Pennsylvania Democratic Party accused the GOP of trying to “manufacture evidence” that counties were not complying with the state order by giving them a day to respond to their request.

Boockvar has said a very small number of ballots are at stake and that the current vote count only includes ballots that arrived by Election Day.

“So I think, no matter what happens, I don’t think it’s going to be a tremendous impact on this race,” she told CNN on Thursday.

In Philadelphia, for example, just 500 ballots came in Wednesday and Thursday and were set aside, according to city officials.

Kevin Feeley, a spokesman for the city commissioners, said Philadelphia might eventually count the ballots, but said they were put aside preemptively in case of a legal challenge.

Allegheny County planned to add the 947 valid ballots it received after Election Day to its total Friday evening, but was keeping them segregated for review, according to county spokeswoman Amie Downs.

In all, the U.S. Postal Service processed roughly 4,900 ballots in Pennsylvania on Wednesday and Thursday, according to agency data. In his order Friday, Alito said that all ballots received by mail after 8 p.m. Tuesday must be kept in a secure and sealed container separate from other voted ballots, and must be counted separately, if counties were including them in their tallies.

The U.S. Supreme Court has twice passed up the chance to block the deadline extension for receiving mail ballots that was approved by the Pennsylvania Supreme Court. But three justices indicated they were open to revisiting the issue, arguing the court’s order might have been unconstitutional. Counties began segregating ballots in response.

Meanwhile, election officials in Clark County urged caution regarding accusations by the Nevada Republican Party that more than 3,000 people voted illegally after moving out of state.

Joe Gloria, the registrar of voters in Clark County, said officials were going through the list of voters provided by the GOP, but noted that it is not unusual for people to legally cast ballots after moving out of the state.

“You don’t have to live here in order to be eligible to vote here,” Gloria said.

Las Vegas is a military town and home to nearby Nellis Air Force Base. Some people leave the state to go to college. Those service members and students are eligible to continue voting in Nevada even if they leave the state, he said.

On Thursday, the Nevada GOP sent information about the allegedly fraudulent votes to U.S. Attorney General William P. Barr. The list of more than 3,000 voters did not include names, but it did show the addresses listed in a national database of where the Nevada voters allegedly moved. Some of the voters gave as their new addresses codes used to send mail to overseas military installations or diplomatic posts.

Representatives of the Nevada GOP and Trump campaign did not immediately respond to a question about whether they were accusing members of the military of voting in Nevada improperly because those voters had moved out of state for service.

A Justice Department official said Wednesday the department was “looking into” the allegations, but declined to provide more detail. A second set of claims were sent to the Justice Department by Republican National Committee Chairwoman Ronna McDaniel, who said during a news conference Friday in Bloomfield Hills, Mich., that election workers were told to backdate certain ballots, without providing direct evidence.

McDaniel acknowledged that her allegations had not been fully vetted, saying “it does take a process” to get from “statement to affidavit to a lawsuit.” She said there should be time to pursue and investigate tips to allay concerns of voters, adding that information had been shared with federal prosecutors. A Justice Department official said the information McDaniel provided has been referred to the FBI. It was unclear what, if any, action they planned to take. An FBI spokeswoman in Detroit referred a reporter to the U.S. attorney’s office, which declined to comment.

McDaniel also alleged that in Rochester Hills, Mich., 2,000 ballots were “found” Thursday night that had been “given to Democrats that were Republican ballots, due to a clerical error.”

Tina Barton, the GOP city clerk of Rochester Hills, said McDaniel was referring to an “isolated mistake that was quickly rectified” and that the claim ballots were missing or found was “categorically false.”

“As a Republican, I am disturbed that this is intentionally being mischaracterized to undermine the election process,” Barton said in a video posted to Twitter.

The speaker of the Michigan House of Representatives, Lee Chatfield, has announced plans to open a legislative inquiry into the state’s election and counting procedures. On Friday afternoon, the three-term Republican called a last-minute meeting of the Oversight Committee on Saturday to launch the effort.

Chatfield said the aim of the inquiry was not to change the results of the election, but for the purpose of accountability and to provide confidence in the results.

“Nothing is more important than integrity in our election system. Every single legal vote needs to be counted,” he said in a statement. “And let me be very clear: whoever gets the most votes will win Michigan! Period. End of story. Then we move on.”

The legislators’ meeting in Lansing will come as pro-Trump supporters are scheduled to demonstrate at the State Capitol building.

Meanwhile, in Arizona, Secretary of State Katie Hobbs (D) on Friday filed an amicus brief in a lawsuit alleging that Sharpies caused ballot problems, asking that the matter be resolved quickly and seeking to dispel “misinformation that undermines the hard work of Arizona’s election administrators, poll workers, and voters.” Election officials have stressed that Sharpie use will not invalidate ballots and that felt tip pens are actually preferred, trying to tamp down rumors that exploded online and spurred protests.

The complaint was filed on behalf of two voters and also cites a poll worker who believes Sharpies caused issues processing most voters’ ballots at a Phoenix mall.

Responding Thursday to questions from the office of Arizona Attorney General Mark Brnovich (R), Maricopa County Attorney Allister Adel said that no ballots were rejected at the county’s voting centers.

Christine Spolar in Pittsburgh; Jon Swaine in New York; Hannah Knowles in Phoenix; Tom Hamburger and Kayla Ruble in Detroit; Maura Ewing and Karen Heller in Philadelphia; and Matt Zapotosky, Jacob Bogage, Felicia Sonmez, Colby Itkowitz, Tobi Raji, Aaron Schaffer, Anna Brugmann and Maya Smith in Washington contributed to this report.