Rogelio V. Solis / AP

There are a few basic facts about Mississippi that would normally be hopeful signs for the Democrat in Tuesday’s Senate runoff, when Mike Espy, the former U.S. secretary of agriculture, will square off against the Republican incumbent, Cindy Hyde-Smith. Mississippi’s voting-age population is 37 percent black, the highest share in the country. The last stretch of the race has featured naked racism against Espy, who is black. And because this is the last major contest of a dramatic midterm season, that racism has become the subject of a national debate, one that has heavily scrutinized Hyde-Smith’s record and raised Espy’s profile.

Yet, like all black candidates for statewide office in the blackest state in the country, Espy has the odds stacked against him. How could a black candidate face such an uphill battle in Mississippi? Why is Mississippi even so deeply Republican? As partisan politics in America realign more and more clearly along racial lines, Espy’s candidacy is an intriguing case study, especially as Democrats attempt to establish stable footholds in the Deep South. The biggest obstacles for black candidates, and Democrats in the South more broadly, are intense racial polarization and an electoral system featuring regularly low turnout. Those obstacles will be instructive for national battles ahead.

That Espy is even within shouting distance of Hyde-Smith might be considered a major victory for Democrats. Donald Trump won the state by 17 points in 2016. Espy, who won 40 percent of the vote in November’s special election, likely only qualified for Tuesday’s runoff because the Republican vote was split. Hyde-Smith, who was appointed by Governor Phil Bryant to fill Thad Cochran’s Senate seat in April, was undercut by the candidacy of Chris McDaniel, a Republican state senator who barely lost to Cochran in a 2014 Senate runoff. Few early polls predicted that Tuesday’s election would be anything more than a formality.

Espy is still not expected to win. According to FiveThirtyEight, a mid-November survey found Hyde-Smith up 11 points, although the poll was conducted by a Republican-leaning firm. But there are signs that he could outperform a traditional Democrat. A heavy dose of national attention on the election, and a fund-raising boost for Espy, should tighten the race.

For Hyde-Smith, the closing stretch has been marked by several charges of racism. In a state that was once the lynching capital of the country, the senator recently commented, when describing a campaign supporter, that “if he invited me to a public hanging, I’d be on the front row.” Hyde-Smith’s campaign has described her remarks as innocuous, and cast the backlash as race-baiting. But in a bizarre press conference during the media frenzy that followed, Bryant dug deeper into racist tropes to defend her, implying that black women were to blame for “the genocide of 20 million African American children” through abortion.

It’s unclear if that episode will hurt Hyde-Smith. Given Mississippi’s history, it might be naive to think so. Charges of racism and of neo-Confederate sympathies are not new in Hyde-Smith’s recent career. News reports have zeroed in on comments she made praising Confederate soldiers, on legislation she endorsed in the state Senate to rename a highway after Confederate President Jefferson Davis, and on a photo of her in a Confederate soldier’s cap with the caption “Mississippi history at its best!”

One report in particular has proved especially controversial nationally: Hyde-Smith’s attendance at a “segregation academy”—a term used throughout the South for private schools that were created in response to public-school integration—and her choice to send her daughter to one, too. But suggestions in the media that their attendance is a liability ignores one pretty basic element: that segregation academies are ubiquitous in Mississippi, and are relatively normal parts of life for much of the white voting base that Hyde-Smith will need to win. Indeed, it’s possible that, as has happened time and again in Mississippi, national scrutiny of local education policy could help her with some white voters. These schools are lasting reminders of the scourge of white supremacy, but the fact is that white supremacy can still win votes.

That fact is reflected in the difficult math for Espy. On the surface, his path to victory is enviably simple. Black people make up about 36 percent of registered voters. While exit polls indicate that they slightly underperformed turnout-wise in the general election, they favored Espy at 90 percent. If he can mobilize enough black voters so that they’re just above their share of the electorate, and if he can secure about 20 percent to 25 percent of the white vote, he’s in the game. A Democratic candidate in just about any other state might welcome those odds.

But Mississippi is not any other state. It might well be considered the spiritual home of voter suppression, with a wave of new voting restrictions overlaid on deeper structural barriers, like racial disparities in criminal convictions, which can bar people from voting. Additionally, according to the Election Law Journal, Mississippi is the worst state in the country for ballot accessibility. Using a measure called the Cost of Voting Index, the Journal found that the real-world financial penalties for Mississippi voters are significantly higher than they are in “the next most costly state,” Virginia. That’s bad news for black voters in Mississippi, which has the second-highest black poverty rate in the country.

Racial polarization plays a role as well. One of the core considerations of the Voting Rights Act of 1965 was the behavior of white southern voters, for whom the strongest predictor of candidate choice was not necessarily their party or policy preferences, but rather the opposite of whoever local black voters wanted.

This bloc voting is still seen today, illustrated time and again in districts and states with large black populations—most recently in rightward moves among white voters during the Obama years. Practically, even among some independents and moderate Democrats, white voters’ likelihood of supporting a Republican often depends on how much black voters favor the Democratic candidate. As the Harvard Kennedy School professor Desmond Ang told me earlier this month, there’s evidence that polarization increased markedly in states and districts monitored under the VRA after the law’s implementation—and as black voter turnout increased.

Mississippi is the modern avatar for this kind of polarization and for low black turnout. To wit: Although former President Barack Obama outperformed the previous Democratic presidential nominee, John Kerry, in the state in 2008, he underperformed relative to his predecessor among white voters. And although the then-senator was buoyed by dramatic spikes in black voting nationwide, in Mississippi black turnout was pretty much static from 2004 to 2008. Obama’s improved showing was still based almost entirely on those black voters shunning the GOP.

There’s a hard limit to the number of votes that can be gained that way. But there’s hope for Espy. Stranger things have happened, and it’s possible that the weight of controversy—along with public pressure from Hyde-Smith’s corporate donors—might swing enough white voters and mobilize enough black voters. Regardless of the victor, Tuesday’s results will be important not just in Mississippi, but nationally, as parties take stock of midterm outcomes and as Democrats especially continue to wrestle with the realities of race. As Jamelle Bouie of Slate noted with prescience four years ago, one potential future scenario in American politics could be a system in which white voters are driven to vote solely in a way that defeats minority-preferred candidates—the way the VRA anticipated.

That is to say, in the future the country might look a little more like Mississippi. If Espy wins, it could mean the state—and thus the nation—is capable of bucking long-established trends. If Hyde-Smith wins, it could mean there’s a little more juice left to the old ways still.

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