BallotWire Briefs — Weekly Election Update (Mar. 23–27)

BallotWire delivers data-driven coverage of U.S. elections at every level—federal, state, and local. We track results, trends, and shifts beyond the headlines.

Top Election Developments

A summary of the most significant election news from the week, including major race developments, candidate activity, and changes that may determine upcoming contests.

Supreme Court Weighs Mail-In Ballot Deadline Case With National Election Implications

The U.S. Supreme Court heard oral arguments on March 23 in Watson v. Republican National Committee, a closely watched case that could determine federal standards for counting mail-in ballots. The case concentrates on whether, under federal law, ballots mailed by Election Day but arriving after Election Day should be counted in federal elections.

The dispute derives from a Mississippi law enacted during the COVID-19 pandemic that permits mail-in ballots to be counted if postmarked by Election Day and received within 5 business days. The Republican National Committee challenged this, arguing that federal law defines Election Day as the sole valid voting date and prohibits the counting of ballots arriving after Election Day. Supporters of the Mississippi law contend that complying with postmark deadlines prevents disenfranchisement from mail delays and assert that states can lawfully set reasonable receipt deadlines for ballots.

The outcome has major legal significance, as dozens of states and Washington, D.C., currently allow mail ballots to be counted post-Election Day if they are postmarked by the deadline. The decision could require many states to amend their election laws and processes, affecting millions of ballots in future federal elections. Should the Court rule against the Mississippi law, states may be legally compelled to revise procedures before fall elections, with a decision expected by late June or early July, affording limited time for compliance.

Missouri Supreme Court Upholds Republican Mid-Decade Redistricting Plan

The Missouri Supreme Court handed down a major ruling on March 24, upholding the state's Republican-drawn congressional map in a 4-3 decision, giving the GOP a potential path to pick up an additional U.S. House seat heading into November's midterms. Missouri currently has six Republican and two Democratic U.S. House members.

The new map, passed by Missouri's Republican-led legislature last September at the urging of President Trump, seeks to shift the district represented by Democratic U.S. Representative Emanuel Cleaver of Kansas City by dividing his district into surrounding areas that lean Republican. Legally, the court's decision allows the legislature to redraw districts more frequently than once per decade, as the majority held that the state constitution's language requires redistricting after a census but does not forbid mid-decade changes. This opens the door for future redistricting attempts outside the traditional cycle, likely to affect political representation in the state.

The ruling does not necessarily settle the matter. Opponents have submitted more than 300,000 petition signatures seeking to put the new map to a statewide vote in November. Republican Secretary of State Denny Hoskins, who supports the redrawn map, has not yet certified those signatures. A separate lawsuit is still pending over whether the new districts violate Missouri's compactness requirements, and another challenge seeks to block the map while the referendum question is resolved.

Stitt Appoints Energy Executive Alan Armstrong to Fill Mullin's Oklahoma U.S. Senate Seat

Oklahoma Governor Kevin Stitt appointed energy executive Alan Armstrong on March 24 to fill the U.S. Senate seat vacated by U.S. Senator Markwayne Mullin, who was confirmed as the new secretary of Homeland Security. Armstrong, 63, was the former executive chairman and CEO of Williams Companies, a major Tulsa-based pipeline operator specializing in the collection, storage, and transportation of natural gas. Under Oklahoma law, Armstrong was required to sign an affidavit pledging not to seek election to a full term, effectively clearing the path for U.S. Representative Kevin Hern, who has already announced his candidacy for the seat and secured an endorsement from President Trump. Republicans currently hold a 53-47 seat majority in the U.S. Senate.

State & Local Spotlight

Coverage of notable state and local election events that may indicate broader political trends or influence higher-profile races.

Democrats Flip Two Florida Legislative Seats, Including Trump's Mar-a-Lago District

Florida held four state legislative special elections on March 24, and Democrats walked away with two victories. In the marquee race, Democrat Emily Gregory flipped Florida State House District 87, which includes President Trump's Mar-a-Lago resort, defeating Trump-endorsed Republican Jon Maples 51% to 49%. The district had been vacant since August, when Republican Mike Caruso resigned to become Palm Beach County clerk, a seat he had won by 19 points in 2024. Trump carried the district by 11 points in 2024. In the State Senate District 14 race, Democrat Brian Nathan flipped the seat defeating Republican State Representative Josie Tomkow 50% to Tomkow's 49%. Democrats have now flipped 30 Republican-held state legislative seats since Trump took office in January 2025.

Billy Webster Enters South Carolina Governor’s Race

Greenville businessman and former White House official Billy Webster announced on March 25 that he is running for the Democratic nomination for Governor of South Carolina. Webster becomes the third Democrat in the race, joining State Representative Jermaine Johnson and attorney Mullins McLeod ahead of the June 9 primary. Webster, who previously worked in both the George H.W. Bush and Bill Clinton administrations and later served as chief of staff to former South Carolina Governor Richard Riley when he was U.S. Secretary of Education, is campaigning on lowering the cost of living, expanding healthcare access, and improving the state’s infrastructure for South Carolinians.

Data & Polling Roundup

An overview of newly released polling and data understandings that help contextualize the current electoral landscape and emerging trends.

Paxton Leads Cornyn in Texas Senate Runoff Poll

A new Quantus Insights poll of likely Texas Republican runoff voters, conducted on March 23, 2026, with 1,217 respondents (±2.8% margin of error), finds Attorney General Ken Paxton leading incumbent U.S. Senator John Cornyn as the May runoff election approaches. The poll shows Paxton receiving 48.8% support compared to Cornyn’s 41.3%, with about 10% of voters still undecided. The poll also found endorsements may have a limited impact on the race, with 70.7% of respondents saying a Trump endorsement of Cornyn would make no difference in their vote and 63.5% saying the same about a Trump endorsement of Paxton. The runoff was triggered after neither candidate surpassed 50% in the Republican primary.

Platner leads Mills in the U.S. Senate Democratic primary, and Democrats lead Collins

A new Emerson College Polling survey of Maine likely voters, based on an overall sample of 1,075 likely voters (±2.9% margin of error), finds oyster farmer Graham Platner holding a commanding lead over Governor Janet Mills in the Democratic U.S. Senate primary, 55% to 28%, with 13% undecided. The same poll also tested general election matchups and found Democrats leading incumbent Republican U.S. Senator Susan Collins, with Platner ahead 48% to 41% and Mills ahead 46% to 43%. The race is expected to be one of the most competitive U.S. Senate contests of the 2026 cycle, as Democrats view Maine as one of their best opportunities to flip a Republican-held U.S. Senate seat.

Sununu Leads GOP Primary, Tied with Pappas in New Hampshire Senate Race

A new Emerson College Polling survey of 1,000 likely New Hampshire voters (±2.9% margin of error), conducted March 21–23, 2026, finds former U.S. Senator John Sununu leading former U.S. Senator Scott Brown in the Republican U.S. Senate primary, 48% to 19%, with 33% undecided. In a potential general election, Democratic U.S. Representative Chris Pappas and Sununu are virtually tied, with Pappas at 45% and Sununu at 44%. Pappas leads Brown 48% to 39%.