I don't think she's announced anything. Schumer is up for re-election in 2028. I can't imagine he'd run again, and I do think it is her seat for the taking.
The only thing that might derail her is if Mamdani fails miserably. I believe that any successes that Mamdani has in NYC will
give ALL progressive Democrats and progressive ideas a boost.
And I don't think he is going to fail miserably. New Mexico just voted for universal daycare. These are policies that make sense and can be enacted.