The decision by Ms. Ramos, a state senator from Queens, is at odds with her frequent criticism of Andrew M. Cuomo, including comments questioning his “mental acuity.”

State Sen. Jessica Ramos turned her back on fellow progressive mayoral candidates Friday — making the shocking move to endorse frontrunner Andrew Cuomo despite previously questioning his mental acuity.

Ramos, who is also running for mayor, says she is staying in the race and will remain on the ballot in order to keep having a voice to advocate for her causes.