Sarah McBride

Delaware Republicans are trying to stir up a challenger for U.S. Rep. Sarah McBride this November.

McBride already has one historic win in her pocket from 2024, now fit with budding political capital after a freshman term on Capitol Hill. And before three GOP hopefuls can attempt to cut that short, they will have to square off in the state's primary election Sept. 15.

That includes a familiar name in John J. Whalen III – who lost to McBride in 2024 by nearly a 16-point margin – as well as the Rev. Earl Cooper and Joseph Arminio. Fellow candidate Lee Murphy withdrew from the race in late July, citing a priority to spend "precious, uninterrupted time with my grandchildren" and family, in a statement online.

Early voting for primary elections starts Sept. 2, while polls on primary day, Sept. 15, will open from 7 a.m. to 8 p.m.

Registered Republicans have until then to learn more about the four candidates at their disposal.

Earl Cooper

Earl Cooper has run for this seat once before, on the other side of the ticket. The former-pastor-turned-business-owner ran against McBride in 2024 for the Democratic nomination, losing to the now-midterm congresswoman, who claimed some 80% of the overall vote.

Cooper has long considered himself Republican, living in Delaware on and off for more than three decades, but he said he had hoped "to see what the race was like" and what weight his name may carry. The father and husband of 43 years had operated one of the state's largest minority-owned heavy highway construction companies for decades, while raising a family and one Delaware golf star with his namesake.

Now in his 60s, Cooper said he couldn't square himself as a Democrat. Returning to the GOP, he credited common "culture war" positions on transgender rights and issues he called difficult to accept "being a man of faith." But such comments did not come up when he discussed issues motivating his run.

"My whole goal is to be able to bring resources back to Delaware. ... [I] really understand how important it is to bring back resources, opportunities, to work with Republicans, to work with Democrats, to be able to find solutions that will be able to meet Delawareans," he said over the phone Aug. 21.

Cooper described a campaign focused on education, particularly hoping to see greater innovation, focus on trade and vocational-technical education and student job opportunities. He also highlighted housing and cost-of-living challenges, alongside senior needs. In an interview, Cooper described this platform as natural, given his previous work mentoring youth and helping employees become homeowners while they earned living wages.

As far as the voice he hopes to bring to Washington, Cooper didn't describe blind agreement or opposition with the current Republican administration.

"All we have heard is opposing everything that this administration needs or speaks on," Cooper said. "And all I'm simply saying is that even a broken clock is right twice a day. We got to get back with trying to look at bipartisan areas, especially in Congress."

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Joseph 'Dr. Joe' Arminio

Dr. Joe calls himself a "truth teller" and a populist. The latter connects to the Wilmington native's hopes that his campaign can speak for working people, while the former may point to his wanting to cut through the noise on national economic issues and more.

Joseph Arminio has a doctorate from the Massachusetts Institute of Technology in political science, concentrated in defense policy and international relations. And though the life-long Republican was born and raised in Delaware, he said, the Wilmington resident in his 70s brought that experience to Washington, DC, for decades as a scholar and "public policy practitioner."

Arminio sought a different U.S. House seat in 2008, having lost to still-sitting Rep. Andy Harris in that Republican primary for Maryland's Congressional District 1, largely on the Eastern Shore. Since then, he has authored about seven books on American policy and history.

The candidate walks into this Delaware primary with several priorities: the economy, national defense, education reform, immigration and upholding the Constitution. Broadly, Arminio echoed President Donald Trump on immigration – calling sanctuary cities "a calamity" – while he also argued proper enforcement first requires a "thriving economy." On climate change, he said it's "not a crisis" here.

Arminio hopes his pitch to voters will set him apart, from his "American Prosperity Plan" aimed at combating private and public debt, to "The Grand Bargain" he would propose in the Middle East. More details can be found on his campaign website. In no uncertain terms, Arminio said he opposes the current war in Iran and supports steering Israel toward a two-state solution, with "essential sovereignty" for Palestinian people.

He also critiqued Democrats' acceptance of AIPAC funding amid today's conflicts. McBride's campaign said she has not accepted AIPAC donations since taking office and plans "to not accept them moving forward."

McBride has accepted a little over $74,800 across various groups focused on Israel-U.S. relations, according to July data on AIPAC Tracker, but that social media site tracks much more than the American Israel Public Affairs Committee, which continues to spark some debate. This summer, McBride also fell among more than 100 House Democrats who broke ranks in a vote to eliminate aid to Israel, though it failed.

Overall, Arminio wants to see the United States remain competitive internationally and "on Main Street."

"I come in as, yes, a Republican, but I also come in as a populist. ... I will be able to find support for these ideas among the Democrats," he said. "There's some overlap here."

John J. Whalen III

John Whalen is running on pledges to combat illegal immigration, curb national debt and bolster national security, according to his campaign site.

The candidate did not respond to Delaware Online/The News Journal requests for this guide, nor were any responses from the Millsboro resident recorded with the 2026 League of Women Voters' election guide.

The lifelong Delawarean, Blue Hen and retired businessman now in his 70s echoes some common MAGA positions online, as his website details promises to curb illegal immigration at the border, alongside "asking the tough questions" on national spending. Two of those include: "Why are we supporting institutions of higher learning that are sitting on millions of dollars in endowments?" and "Why do we continue to spend billions of dollars funding government agencies that have failed to perform the duties for which they were formed?"

He also writes that voters should know he is "Pro Life," with abortion being an issue of morality for him, though he supports certain exceptions.

Armed with degrees in political science, history and criminal justice, Whalen served in the Delaware Department of Public Safety's Division of State Police, for over two decades, as previously reported. He retired in 1997 and formed a residential construction company, largely building houses and additions throughout Sussex County for another 22 years.