When revisions to the state’s teacher evaluation law came before the State Senate late Wednesday night, not a single senator cast a “no” vote.

That’s because nearly all of the Senate Democrats had walked out of the Senate chambers to protest a controversial redistricting deal. While they were out, Senate Republicans made quick work of bills that had already been approved by the Assembly. That included the teacher and principal evaluation bill.

The situation meant that the evaluations bill garnered just 36 “yes” votes. Just four of those votes came from senators who represent the city. Two were from the city’s two Republican state senators and two were from two Democrats who are part of an independent caucus.

In the Assembly, the bill passed 91 to 49 and found only scarce opposition from city representatives. About half of the Assembly members from outside of New York City voted against the bill, but just six of the city’s 64 Assembly representatives voted against the bill. The nay votes came from Inez Barron, James Brennan, Joseph Lentol, Vito Lopez, all of Brooklyn; Staten Island’s Louis Tobacco; and Deborah Glick of Manhattan.

Gov. Andrew Cuomo brought the bill before the Senate and Assembly by terming them “measures of necessity.” That means that the legislators could dispense with the traditional three-day public review period before voting on the bills. And by turning the teacher evaluation bill into a stand-alone bill whose passage would come as part of an annual event known as “the big ugly” — a complex deal over multiple bills — Cuomo ensured that the issue would not interfere with budget negotiations. Originally, he had proposed changes to the evaluation law through the budget amendment process.

The timing came as a shock to principals who have been protesting the evaluation system. But they have readied their promised lobbying ad anyway, and it will appear next week in the Legislative Gazette, an Albany publication, even though it will be too late to influence votes. The principals say they have an ethical responsibility to speak out against a law they believe will hurt schools and teachers.