Charter schools want to piggyback on Gov. Andrew Cuomo’s plan to expand pre-kindergarten across the state. But in order to benefit from Cuomo’s $25 million in pre-K grants, the schools first must win the right to offer pre-K classes.

Pushing for that right is at the top of charter school supporters’ agenda today as they convene in Albany as part of the charter sector’s annual advocacy day. The parents will meet in the Albany Convention Center with more than a dozen legislators, then spend the rest of the day visiting their district representatives.

They’re not the only ones lobbying lawmakers over pre-K this week. On Monday, police chiefs, principals, and education groups from around the state declared their support for Cuomo’s pre-K grants, which represent a fraction of the $385 million that the state spends annually on pre-kindergarten.

The charter sector’s lobbying efforts are not so straightforward, because the state’s 1998 law authorizing the schools grants them the right to serve students in kindergarten to 12th grade only. Legislators would have to change to the law — last revised in 2010 amid heavy controversy — to allow pre-kindergarten in charter schools.

“It’s our job to talk to lawmakers and say to them, ‘Hey, does it really makes sense to a have a program where some really good schools don’t have the ability to do full-day pre-K?'” said James Merriman, CEO of the New York City Charter Center.

Merriman said the sector also wants legislators to revive a bill that would allow charter schools to share resources in order to serve special education students and English language learners. In past years, charter school parents and advocates have lobbied for a variety of legislative initiatives: more schoolsmore funding, and, last year, more of a voice on the city’s local parent councils.

Sources say that advocates should dig in for a tough battle with the Assembly, which includes many Democratic lawmakers who have aligned closely with state and city teachers union on charter schools, which rarely employ unionized staff.

“The union would kill it,” said the source, who said broad legislative support for charter school pre-kindergarten would be unlikely during the session this year.

Carl Korn, a spokesman for New York State United Teachers, said the state union has not decided if it would support allowing charter schools to operate pre-K programs.

But United Federation of Teachers President Michael Mulgrew said he didn’t think charter schools were ready to serve earlier grades.

“The charter school sector needs to deal with some of its more immediate concerns like high student attrition and their low number of special education and ELL children,” Mulgrew said.

It’s not the first time charter schools have sought to wade into early education. Harlem Children’s Zone, which operates two charter schools, had to set up a community-based organization with a separate board of trustees to receive state funds to operate its full-day pre-K programs. And Success Academy Charter Schools dabbled in a “developmental kindergarten” program that admitted 4-year-olds before they graduated to kindergarten. Spokeswoman Jenny Sedlis said that program ended after a year.

This year’s charter sector agenda is largely fueled by the recommendationS made by Cuomo’s Education Reform Commission earlier this year. In its “consensus” report, the commission avoided many of the state’s thorniest issues, and instead focused on less controversial initiatives.

All members of the commission embraced the pre-K recommendations. In its report, the commission highlighted research that shows that the earlier students enter a quality early education program, the better they will do in and out of school later on in life.

Some members wanted the report to more explicitly recommend Cuomo to seek legislation to allow charter schools to have a crack at his grants. Sara Mead, a partner at Bellwether Education Partners, said she thinks the state needs more high-quality providers in order for expanded pre-K to succeed. Charter schools, she said, should be at least an option.

“The issue is not that charter schools should be entitled,” Mead said. “It just doesn’t make any sense to preclUde the charters from offering pre-K when some of them want to do it and have a good history of serving kindergartners.”

Even if charter schools win the right to operate pre-K programs, they still might not be eligible for Cuomo’s funding. That’s because districts without approved teacher evaluation plans aren’t eligible for Cuomo’s grants. New York City remains without an evaluation plan and, even if it eventually adopts one, it would not apply to charter schools.

In New York City, 58,000 students were enrolled in pre-kindergarten programs in 2012, according to the City Council. Most of them attended school for just a half-day, but a growing number, 15,590, attended full-day. About 7,500 pre-kindergarten-aged students weren’t enrolled in any program at all.

Several states already have laws that allow charter schools to operate pre-K programs, according to the report. California, Connecticut, Louisiana, Florida, Texas, Georgia, and Washington, D.C., allow charter schools to operate pre-kindergarten programs. Barbara Morgan, a spokeswoman for the New Jersey Department of Education, said New Jersey also allows charters to operate pre-K programs.

In New York, Merriman said, there is still considerable opposition to charter schools in the legislature, and he conceded that the sector’s lobbying had only a slim chance of success.

“I think, unfortunately, there are still lawmakers who just think that nothing positive should be done for the charter sector,” he said.