Top Republicans are increasingly worried about private polling that paints a dire picture of the midterms — and it's not just the House they're afraid of losing, it's also the Senate.

Why it matters: President Trump has warned Republicans that losing their slim House majority could lead to a third impeachment. But a Democratic takeover of the Senate would be a political earthquake — and neuter his last two years in office.

Zoom in: For the first time, GOP strategists are telling Axios that losing the Senate — where Republicans have a 53-47 majority — is a distinct possibility, and that they'll have to fight harder than expected to keep control.

Operatives say they've reviewed polling that shows the GOP facing competitive Senate races not just in traditional battlegrounds such as Michigan, Maine and North Carolina, but also in conservative states like Alaska, Iowa and Ohio.

Top GOP strategists acknowledge that immigration and the economy — the two issues that drove Trump's win in 2024 — are now liabilities.

"A year ago, I would have told you we were almost guaranteed to win the Senate," one GOP operative who's reviewed internal polling told Axios. "Today, I would have to tell you it's far less certain."