JACKSON, Miss. — A federal judge ruled Friday that he will not immediately block Mississippi's unique, multistep process for electing a governor and other statewide officials, which was enacted at a time of Jim Crow segregation to maintain white rule.

However, in a ruling handed down days before Tuesday's election, U.S. District Judge Daniel P. Jordan III wrote that he has "grave concern" about the constitutionality of part of the process. He left open the possibility of further considering a lawsuit that challenges the process — particularly if a person who wins the statewide popular vote could lose an election in the state House of Representatives.

"The Court will not prejudge those issues, but under those circumstances the case would likely proceed to an expedited trial on the merits at least as to the Electoral-Vote Rule," Jordan wrote.

Mississippi's 1890 constitution requires a statewide candidate to win a majority of the popular vote and a majority of electoral vote, with one electoral vote awarded to the top vote-getter in each of the 122 state House districts. If nobody wins both, the election is decided by the House, and representatives are not obligated to vote as their districts did.

The process was written when white politicians across the South were enacting laws to erase black political power gained during Reconstruction, and the separate House vote was promoted as a way for the white ruling class have the final say in who holds office.

African American plaintiffs who sued the state this year have argued that the system unconstitutionally violates the principle of one person, one vote.

Jordan wrote that the plaintiffs' argument about violation of one person, one vote is "arguably ... their strongest claim." The plaintiffs' attorneys argued that the Mississippi system is similar to a Georgia county-unit election rule that was invalidated by a federal court ruling in 1963.

"They're right," Jordan wrote.

Jordan's order Friday denied a preliminary injunction to block the state from using the multistep process in Tuesday's elections. He raised concerns about the timing of the case, noting that Mississippi's election laws "are not merely statutes that can be revised in one legislative session; they are constitutional provisions that require amendment."

"That process cannot occur before the November 2019 votes are counted or within a short time after the election. Indeed, it was already too late when this suit was filed," Jordan wrote. "But based on Plaintiffs' argument during the hearing, it appears the process could be attempted before the next statewide election cycle. If not, then by that time there would presumably have been a trial on the merits, and the Court could craft its own 'remedial plan' if necessary."

Plaintiffs' attorneys said Mississippi's history of racially polarized voting means that candidates preferred by black voters must receive a higher share of the statewide vote to win a majority of House districts.

Jordan wrote he has "grave concern that at least the Electoral-Vote rule is unconstitutional."

One of the plaintiffs' attorneys, Rob McDuff of the Mississippi Center for Justice, also noted that Jordan said the electoral vote rule eventually could cause "irreparable harm."

"If the electoral vote rule is triggered this time around and puts the House of Representatives in a position to decide the election, it is possible the judge would declare it unconstitutional and require that the candidate with the most (popular) votes be declared the winner," McDuff said.

No other state in the U.S. uses such a method to choose governor, and it's rare for a race to be decided by the Mississippi House. That last happened in 1999, when nobody received the required majorities in a four-person race for governor. The top two candidates were white, and each won 61 electoral votes. House members chose the Democrat who had received the most votes. At the time, the House was controlled by Democrats. It is now controlled by Republicans.

The two major-party nominees for governor this year are Republican Lt. Gov. Tate Reeves and Democratic Attorney General Jim Hood. Both are white, but Democrats generally fare well among black voters and Republicans among white ones.

The lawsuit was filed May 30 against two Republican officials — Secretary of State Delbert Hosemann, who is Mississippi's top elections officer, and House Speaker Philip Gunn, who would preside if there's a House vote to decide a statewide race.

Eric Holder, who was the first African American to serve as U.S. attorney general, is now chairman of the National Democratic Redistricting Committee, whose affiliated foundation is providing financial and legal backing for the lawsuit.

"Today's ruling means that nearly 130 years after delegates at the Mississippi Constitutional Convention put in place an electoral device to dilute the voting rights and power of African Americans, we are one giant step closer to a level playing field for every voter in the state," Holder said in a statement Friday.

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