The final high-profile race of the midterms, Tuesday’s tight runoff between Mississippi candidates Mike Espy and Cindy Hyde-Smith, could produce one of the season’s most momentous outcomes: a black senator from a state that hasn’t elected an African American candidate to a statewide office in more than a century.

On Monday, President Trump campaigned in Tupelo and Biloxi for Hyde-Smith, who has come under attack for her past embrace of Confederate symbols and for her comments about “a public hanging,” which evoked the state’s dark history of lynchings.

"She votes to make America great again and she votes for America first,” Trump said, urging his supporters to turn out for “one of the most important elections of your lives.”

Yet, while the election of Espy, a former congressman who served as secretary of agriculture during the Bill Clinton administration, would be historic, it wouldn’t be unprecedented. The same Mississippi seat was once held by the first African American ever to serve in the U.S. Senate.

Hiram Rhodes Revels, a onetime barber and former Union Army chaplain, came to Washington in 1870, at the start of a remarkable (albeit short-lived) period of what historians call “biracial democracy” in the Reconstruction-era Deep South.

“It was a pivotal moment in American history even though it was shortly overthrown,” said Eric Foner, an emeritus professor of history at Columbia University.

The backlash to black men in power wouldn’t take long to arrive. However, for a brief period immediately after the Civil War, newly enfranchised African Americans would participate widely and freely in electoral politics, putting their candidates in office from courthouses to Capitol Hill. At its peak, at least 15 African Americans served in Congress — some of them former slaves.

Revels was the first. A freeborn native of North Carolina, he was of mixed African and European heritage. After working briefly as a barber, he was educated in Quaker schools and later at Knox College in Illinois. He became a minister in the African Methodist Episcopal Church and served as a teacher and preacher at churches throughout the South and Midwest. He worked in St. Louis, according to his congressional biography, despite the fact Missouri prohibited free blacks from settling in the state, fearing their presence could inspire a slave insurrection.

Revels displayed a strategic restraint that would later serve him well in politics.

“I sedulously refrained from doing anything that would incite slaves to run away from their masters,” he wrote in his autobiography. “It being understood that my object was to preach the gospel to them, and improve their moral and spiritual condition even slave holders were tolerant of me.”

During the war, Revels helped help recruit black troops from Maryland and served as their chaplain. He organized schools for newly emancipated slaves.

“That was the kind of background that black leaders came from,” Foner said. “You had to have some sort of leadership experience.”

After the war, Revels led churches in Mississippi, and his efforts to generate educational opportunities for former slaves attracted the attention of Republican Party officials eager to recruit black candidates for an electorate that was, suddenly, about evenly African American and white. Revels was elected in 1868 to the Board of Aldermen in Natchez, Miss. The next year, he won a seat in the Mississippi Senate, one of more than 30 black members in a 140-man legislature.

At the time, U.S. senators were elected not by the people, but by state legislatures (the 17th Amendment would change that about 30 years later). Mississippi’s legislature, elected by both races, was sworn in just in time to carry out a critical duty: filling the seats of the two Mississippi senators who had left office at the start of the war, including the one held by Confederate President Jefferson Davis.

A deal was struck to select one black senator and one white senator. In 1870, Revels was elected to office with just a year remaining in the term. He was to be not just the first African American member of the U.S. Senate, but also the first to serve in either house of Congress.

“Today we make the declaration a reality,” Massachusetts Sen. Charles Sumner said of Revels’s election, classifying the moment as a fulfillment of America’s founding principle that “all men are created equal.”

Despite the accolades, Senate Democrats fiercely resisted. Because the 14th Amendment had only made black people citizens in 1868, Revels fell short of the Constitution’s nine-year citizenship requirement for senators, they argued.

Regardless, on Feb. 25, 1870, the Senate voted 48 to 8 to seat him. Applause erupted in the galleries, and some gloated that it was Davis’s own delegation that had delivered the first black senator.

The Confederate leader “went out to establish a government whose cornerstone should be the oppression and perpetual enslavement of a race because their skin differed in color from his,” thundered Nevada Sen. James Nye. “Sir, what a magnificent spectacle of retributive justice is witnessed here!”

Revels’s Senate career was brief and moderate. He advocated both for “Negro representation” and universal Confederate amnesty. A year later, not seeking a full term, he returned to Mississippi and became president of Alcorn State University, a historically black land-grant institution.

Mississippi would elect one other Reconstruction-era African American senator, Blanche Bruce, who served a full term, in 1875. Yet, that marked the end of full black participation in Mississippi politics.

White opposition to black representation had been building. An African American congressman from South Carolina was assassinated in 1868, and the Ku Klux Klan was born.

“It was a period of terrorism,” Foner said. “You were risking your life to be a black political leader.”

The election of 1875 was marked by violence and repression, a mob-fueled assertion of white political dominance in the post-Civil War era of Redemption.

“Reconstruction was over,” Foner said.

No African American has been elected by Mississippi’s full electorate since.

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