Despite coming close on occasion, a school voucher program is the piece of Gov. Christie's education agenda that he has never been able to push through - unlike tenure reform, charter schools, and performance pay for teachers.

Christie is making one more run at vouchers in his fourth budget, and his proposal for a modest $2 million pilot is likely to grab the headlines and spark the loudest debate in an education budget nearing $12.4 billion.

The biggest chunk of change is state aid to schools, an $8.9 billion package that Christie wants to boost by 1 percent next year. That translates into a small bump for about two-thirds of New Jersey's school districts, with the balance seeing flat funding and none being cut, administration officials said.

A small fraction of that total, Christie's $2 million "Opportunity Scholarship Grants" program, is a far lighter version of the voucher proposal he backed in 2010, a program that would use corporate tax credits to provide close to $1 billion in vouchers for up to 40,000 students over five years. Almost 20 years in the making, that bill went through many iterations and got close to floor votes before stalling. Just how far will $2 million go? It's enough to award $10,000 vouchers to 200 low-income students in the state's lowest-performing schools, giving them a chance to attend a public or private school outside their district.

"These grants will show that choice can work, even - indeed, especially - in some of our most underperforming school districts," Christie said.

Supporters of the proposed Opportunity Scholarship Act on Tuesday applauded the governor for staying the course.

"It's a start; it's a very important start," said state Sen. Thomas H. Kean Jr. (R., Union), prime sponsor of the bill in the Senate. "It adds some real value to the effort we have been making."

Even some Democratic leaders, including Assembly Speaker Sheila Oliver (D., Essex), didn't dismiss vouchers out of hand. "With a pilot, you find out how it works, what kinds of schools parents choose. I'm interesting in hearing what he has to offer," she said.

Some unexpected dissent came from former backers, who said the proposed program was so small as to be almost insignificant. State Sen. Raymond Lesniak (D., Union), maybe the most outspoken sponsor of the original bill, called it the "teeny, teeny, teeny OSA."

"Urban education needs a huge face-lift, but OSA did not have enough support," Lesniak said before the budget address. "But this is too small a model to have an impact."

Assembly Majority Leader Louis Greenwald (D., Camden) also decried the proposal's size. He had been among those supporting a small pilot, but not this small, he said.

Nonetheless, the proposed pilot will surely face a fight, if only because it opens the door to a bigger program.

The New Jersey Education Association, the teachers union, has largely led the charge against vouchers for two decades, and it didn't sound as if it was giving up. "There is no indication you can do this through the budget process, and given the Legislature has shown no interest in this issue, we don't think it will happen now," said Steve Wollmer, the NJEA communications director.