Trump's political grip on the Republican Party is still strong, which is bad news for Republicans who want to break from him.

• Thomas Massie lost his Kentucky primary to a Navy SEAL Trump backed, after $32 million was spent on the race.
• Trump's endorsed candidates have now won 37 races in a row this cycle, across Pennsylvania, Alabama, Kentucky, Georgia, and other states.
• Massie had been a fan favorite but turned on Trump by voting against the big spending bill and pushing back on Israel policy, and voters punished him.
• Only older voters backed the Trump-picked winner; younger voters stuck with Massie, hinting the gap could shrink in future elections.
• Bond markets are flashing warning signs at the same time, with US 10-year yields up sharply and 30-year yields at a 19-year high.

Outlook: Trump's endorsement will keep deciding Republican primaries heading into the midterms, but rising bond yields could squeeze the spending agenda voters just backed.