TRENTON, N.J.—The most far-reaching education issue facing Christopher Cerf, New Jersey Gov. Chris Christie's pick to lead the state Department of Education, is one he tackled in New York City: evaluating teachers in a tough political environment.

Mr. Cerf would walk into a department with a mandate to revamp the way teachers are graded in ways that affect their pay and job security. People familiar with the matter said he was Mr. Christie's pick to head a department that has been led by an acting commissioner since August, but the governor declined to comment on Friday.

Mr. Christie assigned a task force to recommend by March a rubric for judging teachers and school leaders, giving at least half the weight to "identified measures of student achievement."

In New York, Mr. Cerf was the "architect" of a program to use test data to watch student improvements under specific teachers, said his former boss, Joel Klein, the outgoing chancellor of New York City schools. But in New York, the testing wasn't meant to be linked to pay or tenure, and it was supported by the teachers union under a deal crafted with Mr. Cerf.

In New Jersey, the administration's conflict-ridden relationship with the teachers union is one of the signatures of Mr. Christie's national profile. His task force doesn't include representatives from the New Jersey Education Association, the state's largest teachers union, which says data is an unproven way to evaluate teachers.

But a spokesman for the union struck a hopeful tone. "We're looking forward to meeting him," spokesman Steve Wollmer said. "We regard this as a fresh opportunity with the administration and the department."

Derrell Bradford, a member of the task force and the head of a school-choice advocacy group, said Mr. Cerf will also have to adjust to a bigger and messier playing field than he was used to in the single New York City school district.

"In New Jersey, there are 611 wars going on right now, essentially one in each school district," he said. "The leader of the state department of education is going to have to manage every one of those battles financially and ideologically, and that is way more complex than what they had to do in New York."

Despite working for several years in neighboring New York City, Mr. Cerf is still unknown to many in the education community in the Garden State.

"A lot of people don't know him," said Lynne Strickland, executive director of the Garden State Coalition of Schools, which represents a smattering of parents and administrators from mostly suburban districts.

"It's clear that he's a match with Gov. Christie's reform agenda, and I guess our hope will be that what reform occurs in New Jersey...will be done in the best way for the students in the state," Ms. Strickland said.

The nomination must be confirmed by the Senate.

The chairman of the Senate judiciary committee, Democrat Nicholas Scutari, said he needed to do due diligence on Mr. Cerf but said he didn't see why he wouldn't hold a hearing as soon as possible in the new year. Nominations are often subject to political holds or used as bargaining chips in negotiations.