Times Square was a sea of red yesterday — as some 10,000 crimson-clad teachers rallied in solidarity with their Wisconsin counterparts.

Chants of “We are one!” rang out amid signs reading, “Respect our rights,” and “Republicans, beware: When screwed, we multiply.”

Speakers called the efforts in Wisconsin and elsewhere to scuttle collective bargaining and other negotiated rights “an attack on workers, the middle class and people of color.”

The gathering capped a three-day convention of 3,000 New York State United Teachers delegates at a Midtown hotel.

“We need the politicians to know that we’re the people who keep this country going,” said Lynette Azar, a teacher at PS/IS 180 in Brooklyn.