Teamsters president endorses Republican Sen. Roger Marshall in Kansas Senate race

Sean O'Brien, the Teamsters' top leader and an increasingly prominent figure in GOP politics, threw his union's weight behind a Republican senator's re-election bid in Kansas, a move that underscores organized labor's deepening break with the Democratic Party.

O'Brien endorsed Sen. Roger Marshall for a second term, with Fox News Digital first obtaining the Teamsters general president's statement. Teamsters Local 696, the union's Topeka-based chapter, issued its own endorsement alongside O'Brien's. The backing lands in a state that hasn't sent a Democrat to the Senate in nearly a century, and it signals that one of America's most powerful labor unions sees more to gain from working with Republicans than from sticking with the party that once claimed union loyalty as a birthright.

Marshall sits on the Senate Committee on Health, Education, Labor, and Pensions, a perch that has given him direct influence over the bread-and-butter issues unions care about. O'Brien pointed to that record in plain terms.

"As a member of the U.S. Senate Committee on Health, Education, Labor, and Pensions, Sen. Marshall has been eager to partner with us on legislation that protects workers, even when it requires breaking rank with his own party."

That willingness to cross party lines on labor policy is the thread running through the endorsement. Marshall backed the Faster Labor Contracts Act, sponsored by Sen. Josh Hawley of Missouri, a fellow Republican. He also supported the Warehouse Worker Protection Act, a bill carried by Sen. Ed Markey, a Massachusetts Democrat. And he authored his own Railway Safety Act. The portfolio is bipartisan in its origins but consistent in its aim: pro-worker legislation that a union leader can sell to his membership without apology.

O'Brien's march toward the GOP started at the 2024 convention

The Kansas endorsement didn't come out of nowhere. O'Brien appeared as one of the opening speakers at the 2024 Republican National Convention, a moment that startled Democrats who had long treated the Teamsters as a reliable ally. Since then, his trajectory has only moved further into Republican circles.

On Oct. 30, 2025, O'Brien stood outside the West Wing of the White House for a press conference, flanked by Vice President JD Vance and Transportation Secretary Sean Duffy. The image alone, a Teamsters president shoulder-to-shoulder with a Republican administration, would have been unthinkable a decade ago.

O'Brien also backed the nomination of Markwayne Mullin as Department of Homeland Security secretary. Mullin, one of President Donald Trump's top allies, had previously clashed with O'Brien so sharply that the two men reportedly came close to a physical confrontation. That O'Brien set aside personal friction to support Mullin's confirmation tells you something about how seriously the Teamsters president takes his political realignment. Grudges take a back seat when the policy relationship works.

His alliance with Hawley has deepened as well. The Missouri senator and the union boss have built what Fox News Digital described as a political alliance and friendship, a pairing that reflects a broader populist current within the Republican Party, one that prioritizes working-class economic interests over corporate libertarianism.

Marshall outpaces his Democratic challenger in fundraising and political gravity

Marshall's Democratic opponent is Adam Hamilton, described as the lead pastor of Kansas's largest Methodist megachurch. Hamilton has proven a capable fundraiser, pulling in just north of $4.1 million, according to Federal Election Commission data. But Marshall has raised just over $6.2 million, a $2 million advantage that reflects the incumbent's stronger position in a state where Republicans dominate statewide elections.

The Cook Political Report rates the Kansas Senate race as "likely Republican." Kansas hasn't elected a Democratic senator since the 1930s, when George McGill won a single term before a Republican ousted him. Hamilton would need to overcome not just Marshall's fundraising edge and incumbency but nearly a century of partisan history.

The Teamsters endorsement makes that climb steeper. In competitive races, union backing can move voters in blue-collar precincts and lend a candidate credibility on kitchen-table issues. In a race already tilting Republican, it removes one of the few institutional cards Democrats might have played.

Local 696 President Mike Scribner framed the choice in direct terms.

"We are proud to endorse the candidate in this race who continues to be a voice for the middle-class workers of our great state, and that candidate is Sen. Marshall."

Scribner added that Kansas Teamsters "need someone in Washington who is willing to fight on their behalf" and that Marshall "has shown that he is the person for the job." Those aren't hedged words. They're a full-throated endorsement from a local union leader telling his members that the Republican is their guy.

Marshall's overtime tax bill tied him to a kitchen-table win

Beyond the labor-specific legislation, Marshall led the Overtime Wages Relief Act, which eliminated federal income tax on up to $10,000 of overtime wages for individuals and $20,000 for married filers. The measure was included in President Trump's sweeping legislative package. For union workers who depend on overtime to make ends meet, the bill offered tangible relief, and it gave Marshall a concrete achievement to point to when asking for labor's support.

That kind of deliverable matters more to union members than party labels. O'Brien has made that calculus explicit: he backs candidates who produce results for workers, regardless of the letter next to their name. In Marshall's case, the results include bipartisan co-sponsorships, a committee seat that directly shapes labor policy, and a tax provision that puts money in workers' pockets.

Democrats have watched this pattern develop with growing alarm. The party's broader struggles, from candidate collapses in key races to internal divisions over messaging, have opened space for Republicans to court constituencies that once seemed locked in the Democratic column. Organized labor is the most consequential of those constituencies, and O'Brien's endorsements are the clearest evidence that the shift is real.

O'Brien's statement on Marshall was unambiguous about where the relationship stands and where he wants it to go.

"Sen. Marshall has proven time and time again that he is a friend of labor. We look forward to continuing to work together with Sen. Marshall to fight for the rights of hardworking Americans."

That language, "time and time again," "continuing to work together", signals a durable partnership, not a one-off tactical move. O'Brien is telling his members, and the political world, that this alliance has a future.

Democrats can't afford to keep losing labor's loyalty

For decades, Democrats treated union endorsements as part of the furniture, reliable, predictable, and barely worth a press release. The Teamsters' drift toward the GOP upends that assumption. When the general president of a 1.3-million-member union speaks at the Republican convention, stands with a Republican vice president at the White House, and endorses Republican senators by name, the old coalition math stops working.

The Kansas race itself may not be a cliffhanger. Marshall holds every structural advantage in a state that hasn't wavered from its Republican lean in Senate races since before World War II. But the endorsement's significance extends beyond one contest. It is a data point in a larger pattern: working-class voters and their institutional representatives are finding less and less reason to stick with a Democratic Party that has drifted toward cultural progressivism and away from the economic populism that once held the coalition together.

Marshall earned this endorsement the old-fashioned way, by showing up on labor issues, co-sponsoring bills that matter to workers, and delivering a tax cut aimed squarely at the people who punch a clock. If Democrats want union support back, they'll need to offer more than nostalgia. Right now, the Teamsters are going where the results are.