The most Democratic district in the country is now up for grabs in 2020, and it could draw a large Democratic field to fill it. But for now, a New York City rising young political star is emerging as the early frontrunner.

New York Rep. Jose Serrano, 75, announced this week he won’t seek re-election after being diagnosed with Parkinson’s disease. Serrano was first elected to represent the Bronx district in a 1990 special election after serving in the state legislature for 15 years. He’s risen to become a member of the powerful House Appropriations Committee and the chairman of the Commerce, Justice, Science Subcommittee. He’s also one of only two Puerto Rican-born lawmakers still in Congress, along with fellow New York Rep. Nydia Velazquez (NY-12). New York’s 15th District is nearly two-thirds Hispanic but also has a growing black population of over 30 percent. It has a PVI of D+44, making the most liberal of all 435 congressional districts. Hillary Clinton carried it in 2016 with 89 percent of the vote, while Barack Obama won 94 percent four years

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