On October 8, 2025, the marble halls of the U.S. Supreme Court echoed with arguments that could reshape how millions of Americans cast and count their votes. At the center of the storm: a challenge led by Rep. Mike Bost, a Republican from Illinois, who has taken aim at his home state’s law allowing the counting of mail-in ballots postmarked by Election Day for up to 14 days after the polls close. The outcome of this case, Bost v. Illinois Board of Elections, could reverberate far beyond Illinois, potentially influencing similar laws in more than half the states.
The case, as reported by Roll Call and The Center Square, stems from a lawsuit Bost filed in 2022. He contends that Illinois’ extended ballot-counting window violates federal law, which sets a uniform Election Day for federal races. Bost and a group of Republican presidential electors argue that allowing ballots to trickle in for two weeks after Election Day undermines the integrity of elections—and, crucially, could affect the outcome of tightly contested races.
The Supreme Court’s oral arguments revealed a sharply divided bench. Some justices, including Chief Justice John Roberts and Justice Brett Kavanaugh, expressed deep concerns about the prospect of candidates being forced to challenge vote-counting rules only after an election’s outcome is known. Roberts, addressing Illinois’ attorney, warned that “preventing such lawsuits ahead of the election would mean any challenges to the counting are going to be in the middle of the most fraught time for the court to get involved in electoral politics.” He didn’t mince words, calling the scenario “a potential disaster.”
Justice Kavanaugh echoed this unease, saying, “I’m worried about the chaos of post-election litigation and how that would play out in a circumstance like a challenge to this particular ballot counting rule in particular.” Both justices seemed to favor allowing pre-election challenges to avoid the ugly spectacle of courts wading into election disputes after votes have been cast and the stakes are at their highest.
On the other side, several justices appointed by Democratic presidents were skeptical of Bost’s claims of harm. Justice Ketanji Brown Jackson pressed Bost’s attorney, Paul D. Clement, to explain how the Illinois law actually injured the congressman. “In every election, candidates voluntarily put themselves up for election and there is a risk that they will win or lose,” Jackson noted, according to The Center Square. She cautioned against watering down the standard for filing a federal lawsuit—known as standing—by allowing speculative harms to suffice. “It seems to me crucial to uphold this idea that harm is required for standing purposes,” she said, adding that Bost’s logic could open the floodgates to post-election challenges from losing candidates simply seeking to change their margin of defeat.
Justices Elena Kagan and Sonia Sotomayor also questioned the real-world impact of Illinois’ ballot-counting rules. Kagan compared the situation to other election law disputes, such as restrictions on early voting, and wondered whether mere dissatisfaction with a rule is enough to warrant federal court intervention. Sotomayor pointed out that Bost’s case seemed rooted in speculation rather than demonstrable injury.
Illinois, for its part, staunchly defended its law. Jane E. Notz, the state’s solicitor general, argued that more than half of U.S. states have similar provisions—many dating back to the Civil War, when they were designed to ensure soldiers’ votes were counted. Allowing Bost’s lawsuit to proceed, Notz warned, “would cause chaos for election officials while saddling federal courts with resolving abstract policy disputes over election rules.” She emphasized that Bost’s “smaller margin of victory does not have real-world consequences.” Notz further explained that Illinois already counts provisional ballots up to two weeks after the election, making it hard to prove that mail-in ballots alone cause harm or require additional campaign resources.
But not all the justices were convinced. Justice Samuel Alito, joined by Kavanaugh, suggested that even a reduced margin of victory or added campaign expenditures could constitute harm. They pressed Notz on whether Bost’s team would need to expend resources monitoring the ongoing count, potentially affecting the candidate’s interests. Clement, Bost’s attorney, seized on this point: “The candidate is not a bystander in his or her own election,” he argued, insisting that any uncertainty or added burden imposed by extended counting periods is inherently harmful. “Allowing Bost’s lawsuit simply requires acknowledging that candidates have a unique concrete and particularized interest in the rules of the electoral road, especially those that address which ballots are going to be counted and when.”
The Trump administration has also thrown its weight behind Bost’s challenge. Michael Talent, assistant to the solicitor general, argued that without the ability to challenge such laws, “the candidate is forced to gamble that the rule is not going to cost him the election.” This sentiment echoes broader Republican concerns about mail-in ballots—a flashpoint since the 2020 election. Former President Donald Trump, in an August 2025 social media post, vowed to “lead a movement” to end mail-in ballots and voting machines, promising to sign an executive order to that effect. “Remember, the States are merely an ‘agent’ for the Federal Government in counting and tabulating the votes,” Trump wrote. “They must do what the Federal Government, as represented by the President of the United States, tells them, FOR THE GOOD OF OUR COUNTRY, to do.” Although Trump issued a related executive order earlier this year, seeking to override state laws that allow counting of ballots arriving after Election Day, that order is currently on hold amid multiple court challenges.
Challenges to late-arriving ballot counts are not new. After the 2020 election, similar arguments formed the backbone of dozens of unsuccessful lawsuits from Trump and his allies, all aiming to overturn results in key states. Yet, as Illinois has pointed out, the practice of counting ballots postmarked by Election Day but received later has deep historical roots and is hardly unique to one party or region.
What’s at stake in Bost v. Illinois Board of Elections is not just the fate of one state’s mail-in ballot law, but the broader question of when and how federal courts should intervene in the complex machinery of American elections. If the Supreme Court sides with Bost, it could open the door to a wave of lawsuits challenging similar laws in dozens of states—dramatically raising the stakes for future elections. Conversely, if the court upholds the lower court’s decision to dismiss the case as too speculative, it may reaffirm the longstanding principle that only concrete, demonstrable harms can bring a candidate into federal court before the votes are counted.
For now, all eyes are on the Supreme Court. As the justices weigh the delicate balance between election integrity, voter access, and judicial restraint, the nation waits—wondering whether the rules of the electoral road are about to change yet again.
