ASG officials estimated Monday that the Feb. 20 event would cost $12,910 if 1,400 students participate.
But ASG officials are still hoping that 2,000 to 2,500 students will participate, potentially increasing the cost to $20,000.
Harold Pettigrew, N.C. State University student body president, questioned the dedication of the system schools to the lobbying day.
"I'm not seeing a full commitment by all the universities," Pettigrew said. "This is supposed to be an initiative across the state, not just one or three schools."
N.C. State plans to send 700 students -- more than seven times the number from other schools -- and provide $5,000 in funding.
Chris McClure, UNC-Chapel Hill's lone delegate, said at least 40 UNC-CH students would attend but did not say how much money the school would provide.
Pettigrew asked that other universities set a minimum amount to contribute before he could request funding from the N.C. State Student Senate.
But no other school could determine how much money it could contribute.
Charles Lawley III, an N.C. State delegate who is working to organize the lobbying day, said commitment from other schools is vital for the request's approval.