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.”

The Queens senator will put her support behind Cuomo at an 11 a.m. event at the District Council of Carpenters Headquarters, her campaign confirmed.

In an extraordinary about-face, back-of-the-pack mayoral candidate Jessica Ramos is endorsing her front-running rival Andrew Cuomo — just weeks after questioning his “mental acuity”