Lt. Gov. Anthony G. Brown asked state lawmakers Wednesday to endorse a key plank in his platform for governor: increasing access to pre-kindergarten classes.

State legislators are weighing a small expansion of Maryland's program, which already provides half-day preschool to about 29,000 students from low-income families.

Brown pitched the $4.3 million initiative to fund 1,600 more seats as "a modest step" toward his long-term goal of providing free, all-day pre-kindergarten to every Maryland 4-year-old.

"There are still too many children who don't have access to quality pre-K, and these children are in danger of being left behind," he told the House Ways and Means Committee.

Education advocates and all three Democrats in the race for governor have embraced early childhood education as a crucial policy goal for the state. Much research shows that disparities in vocabulary among students entering kindergarten can put students behind for the rest of their educational careers.

The cost of providing quality pre-kindergarten to every child, however, is more than $120 million a year, according to legislative analysts. And while the Democratic candidates each support some form of expansion, the candidates differ on how quickly and how much they would expand it.

Brown's campaign for governor used Wednesday's hearing to launch an attack against Attorney General Douglas F. Gansler's more limited approach, which would offer all-day pre-school but only to low-income students. Gansler has said the state cannot afford to launch a universal program now, and the all-day programs better accommodate working parents.

"This is yet another instance in which Doug Gansler is woefully out of step with Maryland Democrats," Brown's campaign manager, Justin Schall, said.

In an interview, Gansler defended his position as a targeted and logical approach to closing the achievement gap between lower- and higher-income students. He said while the state's long-term goal should be universal pre-kindergarten, the state would "have to cut other things" to come up for the money to pay for it.

Del. Heather R. Mizeur of Montgomery County, the other Democrat in the race, has proposed legalizing and taxing marijuana to more quickly fund pre-K programs for all Maryland children.

The state already spends about $103 million a year to provide half-day pre-kindergarten to some students. Brown's proposal would create a pool of grant money, which private and public pre-kindergarten providers could apply for and use to expand existing programs. Gov. Martin O'Malley, who has endorsed Brown in the contest to replace him as governor, has already included $4.3 million in the budget for the pre-kindergarten expansion.

Under the state's existing pilot program, families who earn 185 percent of the poverty level — roughly $40,000 a year — are eligible for free pre-kindergarten. Brown's plan would raise that income threshold to 300 percent of the poverty level, which translates to about $70,000 for a family of four.

Democrats who support the program, and some Republicans, questioned whether Brown's proposal, which relies on the Maryland Department of Education to distribute grants, would have any measurable impact if those 1,600 seats were dispersed throughout the state. And they also questioned whether it was fair to offer free pre-K only to some students when other families who are also struggling would have to pay about $10,000 a year for it?

"I don't want to have any child in Maryland to be at a disadvantage because of the income situation of their parents," said Del. Jay Walker, a Prince George's County Democrat.

Republican Del. Kathryn L. Afzali of Frederick County wanted Brown's assurance that passing this plan would not require parents to send their youngsters to preschool if they didn't want to. "I, for one, kind of resent that," she said.

Brown said the program would be voluntary.

ecox@baltsun.com