Rep. Joe Kennedy (D-Mass.) made the long-awaited announcement Saturday that he'll challenge Sen. Ed Markey (D-Mass.) for his seat in 2020. The 38-year-old said he plans to change Washington from the Senate. "Donald Trump has forced a reckoning without question," he said to a crowd in a community center in East Boston. "But to meet this moment it requires more than just beating him, it requires taking on a broken structure that allowed him to win in the first place." Kennedy has an early lead on Markey in the polls, but Markey — who, like Kennedy, is considered a progressive — has a lot more institutional support. The Democratic Senatorial Campaign Committee, Rep. Alexandria Ocasio-Cortez (D-N.Y.), and Sen. Elizabeth Warren (D-Mass.) all support the incumbent, for instance.

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