U.S. Senate

Democrats must flip at least four seats to gain the majority, and the Cook Political Report ranks nine Senate contests as toss-ups or extremely close. Henry Olsen, a senior fellow at the Ethics and Public Policy Center and a globally recognized expert on American elections and policy, noted the party must win at least one of three seats in the heavily Republican states of Iowa, Texas, and Alaska while also recapturing Ohio, Maine, and North Carolina and holding onto vulnerable seats in Michigan and Georgia.

If Republicans beat back the Democratic challenger in Maine and are victorious in Michigan, Olsen argued it’s unlikely they would lose in Iowa and Texas: “These races aren’t independent variables,” he said.

Alaska

Republicans’ biggest problem in the country’s largest state isn’t the Democratic candidate. It’s another Republican—one who happens to have the same name as incumbent Republican Sen. Dan S. Sullivan, a Marine Corps veteran who has held the seat since 2015. The party filed a lawsuit accusing Democratic nominee Mary Peltola of conspiring with Republican Dan J. Sullivan, a former teacher, to join the race and confuse voters. In Alaska’s primary, the top four vote-getters advance to the general election, and the state’s Supreme Court ruled the second Dan could remain on the ballot.

Maine

Incumbent Susan Collins, the Senate’s longest-serving Republican woman and one of the body’s most bipartisan members, initially faced off against Democrat Graham Platner. But the ex-Marine oyster farmer ended his scandal-ridden campaign on July 8 after key Democratic figures revoked their endorsements following sexual assault allegations. Troy Jackson, who originally placed third in the state’s Democratic primary for governor, won the most delegates during the hasty process to replace Platner on the ballot. The fifth-generation logger and former state senator is neck and neck with Collins in the toss-up race.

Iowa

The Hawkeye State last elected a Democratic senator in 2008, but the possibility doesn’t seem so remote this election cycle. In June, Cook shifted the race closer to uncertain territory, moving it from “likely Republican” to “leans Republican” to “toss-up.” Democrat Josh Turek, a state representative and two-time Paralympic gold medalist with a track record of winning in conservative areas, is so far holding his own against Republican U.S. Rep. Ashley Hinson. The pair are competing in an open race to replace 12-year Senate veteran Joni Ernst, who announced her retirement in September 2025.

Texas

Democrat James Talarico is rapidly gaining ground in this open race that is now considered a toss-up, according to Cook. Talarico, a state representative known for interweaving progressive ideology with his Christian faith, is facing off against Republican Ken Paxton. The state attorney general received Trump’s endorsement and bested incumbent John Cornyn, who held the seat for almost 24 years. Despite the state’s strong Republican lean, many in the party worry Paxton’s personal scandals could cause enough of Cornyn’s strongest supporters to boycott the ballot box, propelling Talarico to victory.

Michigan

The Great Lake State quickly became one of the most heated battlegrounds between moderate Democrats and those edging to the party’s left flank. The U.S. Senate candidate Abdul El-Sayed, endorsed by prominent progressives such as Elizabeth Warren and Alexandria Ocasio-Cortez, triumphed in the Democratic primary and is competing against former U.S. Rep. Mike Rogers, a Republican and former FBI agent.

Ohio

Republican Jon Husted has only held his seat for about two years. Gov. Mike Dewine appointed Husted, a former state senator and secretary of state, after JD Vance left the seat empty to assume the vice presidency. Husted’s opponent, Sherrod Brown, served in the Senate for three terms before losing to Republican challenger Bernie Moreno in 2024. Brown has outraised Husted, but polls indicate an almost deadlocked race. As senator, Brown co-sponsored the Freedom to Travel for Health Care Act, legislation designed to prevent state and local governments from restricting travel across state lines for women seeking abortions.

See our Election Day guide for more races to watch: House and state showdowns.