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- Rep. Alexandria Ocasio-Cortez doubled down on her support of President Joe Biden.
- The New York Democrat said "the matter is closed" and Biden is the party's nominee.
- Some House Democrats have called for Biden to step aside following his disastrous debate performance.
Rep. Alexandria Ocasio-Cortez of New York has declared she is firmly behind President Joe Biden, even as some of her fellow House Democrats continue to fret about the president's standing.