By Jamie Ross and Izin Akhabau

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Good morning. It’s Wednesday, Aug. 19, and we’re glad Carl the dog is ok after spending 17 hours on a cliff ledge last week. The drone footage of the rescue is quite something. Let’s catch up.

	A democratic socialist scored a stunning upset in a Senate primary in Florida.

• Factional fight: State Rep. Angie Nixon defeated a former national security official, Lt. Col. Alex Vindman, despite his cash advantage. The result is a blow for establishment Democrats.

• In other key Florida races: Rep. Cory Mills (R) lost his primary after sexual misconduct allegations. And voters picked two contenders to succeed Republican Gov. Ron DeSantis.

• Primaries took place across four states: Find eight surprises and takeaways here.

President Donald Trump gave Canada a last-minute reprieve from 50% tariffs.

• The tariffs were set to take effect overnight: But, hours before the deadline, Trump said he would hold off for three days. He cited progress in a deal without offering details.

• Tariffs are central to Trump’s economic policy: He credits them with reviving the manufacturing sector. But economists told The Post that Trump is providing only part of the picture.

• Meanwhile: The bond market is trying to say something — it isn’t good.

	The Pentagon is weighing a smaller U.S. presence in the Gulf once the Iran war ends.

• Under consideration: Officials are assessing whether to pull back troops from the Persian Gulf, where U.S. military bases have been battered by months of Iranian strikes.

• Why it matters: The discussions offer an early sign of the war’s potential to transform the region. For decades, Gulf allies have depended on U.S. forces for their defense.

One of Trump’s most loyal and longest-serving aides is in the spotlight.

• Who? Natalie Harp, a 35-year-old aide. Sen. Jon Ossoff (D-Georgia) referenced her at a rally last weekend while criticizing Trump. Find out all you need to know about her here.

• In other administration news: Trump is expected to pick Heidi Overton, another White House aide, to succeed Marty Makary as the next leader of the Food and Drug Administration.

	We found cops who misused Flock cameras. Even their bosses were unaware.

• What to know: Flock’s nationwide network of AI-assisted roadside cameras record passing license plates into a database. A Post investigation found officers used it as a stalking tool.

• Since that investigation: Two officers accused of misusing Flock have been disciplined. Their departments and many others did not have basic procedures for monitoring its use.

A promising vaccine could become the next frontier in cancer treatment.

• You’ve probably heard of mRNA: This technology was behind the leading covid vaccines that helped end the pandemic. Researchers have been exploring its use in cancer treatment.

• This morning: Researchers said a drug that uses mRNA to deliver a vaccine customized to a patient’s tumors effectively prevented skin cancer recurrence in a clinical trial.