As is often the case in primary elections, there are important takeaways about the state of politics and both parties. Tuesday’s results should be a warning to Republicans and Democrats alike as they look ahead to the midterms this fall.

As seen earlier in the Ohio, Indiana and Nebraska primaries, former President Donald Trump’s “Complete and Total Endorsement” is still the most valuable backing out there for Republican primaries—but not a guarantee of victory. As of now, Mr. Trump is 3-2 in Tuesday’s six competitive Republican primaries, with the Pennsylvania Senate race (in which he backed Mr. Oz) still up in the air.

Mr. Trump’s favorite prevailed in the North Carolina Senate primary. Aided by almost $12 million in spending by the Club for Growth, Rep. Ted Budd earned an impressive 59% of the vote. After receiving the former president’s blessing last week, state Sen. Doug Mastriano won the Pennsylvania gubernatorial contest with 44%. In North Carolina’s 13th Congressional District, the Trump-approved 26-year-old college football star Bo Hines took 32% to capture the Republican nomination for the open seat.

The results went against Mr. Trump’s endorsed candidates in North Carolina’s 11th congressional district, where the controversial Rep. Madison Cawthorn was defeated for renomination by state Sen. Chuck Edwards, and in Idaho, where incumbent Gov. Brad Little easily beat Trump-backed Lt. Gov. Janice McGeachin 53% to 32%.

A second takeaway from Tuesday’s results is that Republicans have a real enthusiasm edge. In the Pennsylvania primaries, with potentially tens of thousands of ballots to be counted, at least 1.33 million Republicans voted, compared with 1.2 million Democrats. In the last midterm primaries, four years ago, at least 737,312 Republicans and 775,660 Democrats voted in the Keystone State. As of this writing North Carolina Republican turnout totaled 759,554 while Democratic turnout was 613,170. Four years ago, 294,295 Republicans and 431,875 Democrats turned out in the Tarheel State primaries for Congress. The GOP turnout increases of 80% in Pennsylvania and 158% in North Carolina should worry Democrats.

A third takeaway is that each party is fractured with discontented elements aiming for dominance. This was most visible in the GOP in Pennsylvania. A late surge by Senate hopeful Kathy Barnette caused Republican bigwigs, worried the party was on the verge of nominating an unvetted candidate with enormous baggage who could lose the Senate seat, to take action. Mr. Mastriano prevailed in his bid for the GOP’s gubernatorial nomination despite—or perhaps because of—his claims that the 2020 election was rigged. This sets up a test in a key battleground state of Mr. Trump’s prospective 2024 message, namely that the last presidential election was stolen. If Mr. Mastriano fights on this ground, rather than on the economy, education, crime, energy and providing a check and balance on President Joe Biden’s agenda, the country will have a preview of what 2024 will look like if Mr. Trump runs again.

The Democrats’ schism is visible in several important races in which progressives beat out more traditional liberals. In Pennsylvania, left-wing Lt. Gov. John Fetterman took 59% and every one of the state’s 67 counties, defeating Rep. Conor Lamb, a more traditional Democrat. Progressive Jamie McLeod-Skinner appears to have beaten incumbent centrist Democratic Rep. Kurt Schrader in Oregon’s Fifth District, which may put this swing seat into play in November. Progressives appear to have won contests in North Carolina’s Fourth District and Oregon’s Sixth, while a Bernie Sanders -endorsed candidate in Pennsylvania’s 12th District is hanging on to a narrow lead, despite being pummeled by spending from a super PAC organized by moderate Democrats. These last three districts are unlikely to be competitive this fall, meaning the ranks of the Squad and the House Progressive Caucus will grow.

Tuesday’s primaries confirmed that angry and highly energized factions are increasingly defining both parties; as a result, America’s politics continues to polarize. The turbulence will increase as the fall election approaches. Buckle up.