Despite a GOP-favored map, Inside Elections invesigates how Trump-era volatility makes 2026 a true Senate toss-up.
Nineteen months out from Election Day, one thing is clear: the 2026 Senate battleground will be shaped by uncertainty — and opportunity. While historical trends and partisan maps seem to favor Republicans, the aggressive posture of the Trump administration, early economic turbulence, and a series of key Democratic retirements have created an unusually volatile landscape.
Nathan L. Gonzales and Jacob Rubashkin of Inside Elections caution against prematurely declaring a winner:
"Republicans are still favored to hold the majority... but it’s unnecessary and even unwise to rule out the unique set of circumstances required for Democrats to win a majority."
As we head into the heart of the cycle, six Senate races deserve special scrutiny: Georgia, Michigan, New Hampshire, Minnesota, Maine, and North Carolina. Here's why these contests could reshape control of the upper chamber and why Democrats' path to a majority, while narrow, remains very much alive.
Sen. Jon Ossoff (D-Ga.) will face re-election in a state where Republicans feel confident about their chances. Ossoff flipped Georgia in the 2020 runoff by a slim margin (51%), but 2024 confirmed that the Peach State retains a distinct red lean at the presidential level.
Sen. Jon Ossoff United States Senate, Wikimedia Commons.
Republicans are awaiting a key decision from Gov. Brian Kemp about whether he will challenge Ossoff. According to Gonzales and Rubashkin, Kemp’s potential candidacy has "frozen the field," deterring other major GOP figures like Reps. Buddy Carter and Rich McCormick.
Regardless of who emerges, Republicans believe Ossoff will be vulnerable. Yet Ossoff boasts a formidable early advantage: he raised an astonishing $11.1 million in the first quarter of 2025, with $11 million cash on hand, according to the AAPC report. This financial firepower and the organizational strength built since 2020 cannot be underestimated.
Gonzales and Rubashkin note that the retirement of Sen. Gary Peters (D-Mich.) has unleashed a scramble on both sides of the aisle.
Sen. Gary Peters, US Senate Photography, Wikimedia Commons
On the Democratic side, rising stars like State Sen. Mallory McMorrow and former Wayne County health official Abdul El-Sayed have already entered the race. Rep. Haley Stevens and former House Speaker Joe Tate are also actively preparing campaigns.
For Republicans, former Rep. Mike Rogers has officially announced a Senate run. After narrowly losing a House race last cycle, GOP strategists hope he will now face a smoother path to the nomination. National Republican Senatorial Committee Chair Tim Scott and Senate Majority Leader John Thune have endorsed him.
Michigan remains critical: Trump carried the state in 2024, but by a narrow margin. As Inside Elections noted, the Democrats’ chances may hinge on fielding a candidate who can appeal to Detroit’s suburbs while containing Republican gains among working-class voters statewide.
The decision by Sen. Jeanne Shaheen (D-N.H.) to retire triggered one of the most intriguing Senate contests of the cycle.
Sen. Jeanne Shaheen, official U.S. Senate portrait (2021). Photo by U.S. Senate Photographic Studio, John Klemmer. Public domain.
Gonzales and Rubashkin mention that Rep. Chris Pappas has already launched a campaign, and former Obama administration official Maura Sullivan is also running. A bitter Democratic primary looms, potentially weakening the eventual nominee.
On the Republican side, former Sen. Scott Brown — who previously lost Senate races in both Massachusetts and New Hampshire — is contemplating another bid. While Brown’s electoral track record is spotty, GOP strategists regard him as a credible investment given his national name recognition.
New Hampshire typically leans Democratic in presidential years, but narrow margins and an unsettled electorate offer Republicans a legitimate pickup chance — especially if the national mood turns sour for the party in power.
In Minnesota, Sen. Tina Smith’s (D-Minn.) retirement also opened a fiercely competitive primary.
Sen. Tina Smith. U.S. Senate Photographic Studio, Wikimedia Commons
Lt. Gov. Peggy Flanagan declared her candidacy early, but faces serious opposition from former Senate Minority Leader Melissa Lopez-Franzen and potentially Rep. Angie Craig. This internal battle reflects broader tensions between the progressive and pragmatic wings of the Democratic Party — a tension that Inside Elections flagged as a growing problem nationally.
Meanwhile, Republicans are desperate to avoid repeating 2020 when Royce White captured their Senate nomination. This year, former Navy SEAL Adam Schwarze and other establishment-backed candidates are moving early to secure the GOP spot. Although Minnesota has trended Democratic, Harris’s 2024 margin was just 4 points — a sign that in a red-wave scenario, even this Midwestern stronghold could be in play.
Sen. Susan Collins (R-Maine), a longtime GOP survivor in a blue-trending state, is running for re-election. Though she survived a tough challenge in 2020, this cycle presents different dynamics.
Sen. Susan Collins. United States Senate, Wikimedia Commons
For one, Maine voters may be more open to punishing Republicans during a Trump midterm, especially if executive overreach or economic instability sours public opinion. As Gonzales and Rubashkin put it,
"This will be the first time [Collins] is up for re-election in the midterm of a Republican president since 2002.”
Democrats lack a top-tier challenger for now, but possibilities include outgoing Gov. Janet Mills, Rep. Jared Golden, and even new figures like political operative Jordan Wood. Collins’ traditional brand of moderation remains her strongest shield — but it may not be as invulnerable as it once was.
Sen. Thom Tillis (R-N.C.) enters 2026 as a perennial battleground incumbent. Having won in both 2014 and 2020 by 49%, Tillis has never posted a majority victory and remains one of the GOP’s more vulnerable figures.
Sen. Thom Tillis. United States Congress, Wikimedia Commons
Former Gov. Roy Cooper is considered Democrats’ "Plan A through Z" for this race, according to Inside Elections. However, if Cooper passes, other Democratic options include Lt. Gov. Rachel Hunt and former EPA Administrator Michael Regan.
On the Republican side, Tillis could face a primary challenge from Trump-aligned conservatives unhappy with his more establishment-friendly record. North Carolina’s suburban growth — especially around Raleigh and Charlotte — continues to edge the state closer to true tossup status, making this race a major Democratic pickup target.
Looming over all these races is the Trump presidency itself. Inside Elections highlights two plausible but opposite scenarios:
Already, Trump’s aggressive push to expand executive power and his volatile foreign policy have created higher-than-usual midterm uncertainty. In the words of Gonzales and Rubashkin:
"It’s possible that voters punish Republican candidates over Trump’s overreach... [but also possible that] economic growth fosters voters’ sense of security."
Candidate recruitment, fundraising, and early media narratives will matter more than ever as parties try to frame 2026 either as a referendum on Trump or a choice between competing visions for the country.
At this early stage, Republicans are objectively better positioned to maintain Senate control. They have a favorable map, a strong structural advantage, and a larger initial cash advantage in some battlegrounds.
But Democrats have shown resilience before. In 2022, they bucked historical trends. And the volatility of Trump’s political style could scramble expectations in ways neither side fully anticipates.
As Nathan L. Gonzales and Jacob Rubashkin wisely observe:
"It’s healthy to be open-minded about what could happen in next year’s midterm elections.”
In 2026, open-mindedness may be the only safe bet of all.
