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Good morning.

Here’s what you need to know:

Five months to the midterm elections

• Gavin Newsom, the Democratic lieutenant governor of California and former mayor of San Francisco, captured one of two spots on the November ballot for governor. He will face John Cox, a Republican businessman backed by President Trump, in a state that Mr. Trump lost by nearly four million votes in 2016.

New Jersey could prove as crucial as California in the contest for the House in November. Democratic leaders are hoping to flip as many as four of the five Republican-held districts in the state, and a former Navy pilot and a pro-gun state senator are among those who secured nominations.

• Eight states held primaries on Tuesday, and results are still coming in. Follow live updates here.

Global trade rumblings

• One possible upshot of any deal that President Trump might strike with Kim Jong-un on June 12 in Singapore: more trade between North Korea and China.

On a trip to the countries’ border, our Beijing bureau chief saw a shadow economy of cash couriers, short-term workers and gray-market traders that has persisted despite years of sanctions against North Korea. She also found excitement about the opportunities that the easing of sanctions could bring.