If the election is successful, Maryland will join 10 states, including Illinois, Washington and Oregon, that have unionized since 2005, and family child care providers in the state will become members of the Service Employees International Union Local 500, or SEIU.
SEIU Local 500 represents roughly 10,000 education, government and community services workers in Washington D.C. and Maryland.
Unionizing the state's family child care providers could affect up to 70,000 children in Maryland, said SEIU spokeswoman Sadie Crabtree.
The election has been going on for two weeks.
"We expect the announcement is going to be positive," Crabtree said.
Maryland has lost nearly 3,000 licensed family child care providers since 1994, SEIU said. According to the union, Maryland providers earn an average $15,840 a year, after subtracting operating expenses.
In Frederick, said Shannon Aleshire, the director of Frederick County's Child Care Choices, the organization is losing providers every month, despite the county's population explosion. Nine years ago, when she joined the agency, there were about 730 providers, an number that has since decreased to 500.
Aleshire thinks stiffer state regulations may have contributed to the decline, although the precise reasons why have been difficult to track.
She could not comment on unionization plans.
The dearth of providers in the state has made it hard for working parents to find someone to cheaply take care of their children.
"Child care has become a crisis for children, parent and providers," said Madie Green, a District Heights provider for more than 25 years, in an SEIU statement.
"Parents are struggling to find affordable, quality child care, but a lot of providers just can't afford to keep our doors open."
Unionizing will include allowing negotiation with the state for more training opportunities, access to affordable health care, and better reimbursement from Maryland's childcare assistance program, according to the SEIU.
The election has been opposed by the Maryland State Family Child Care Association, a non-profit organization that has represented family providers in Maryland since 1983, according to a position statement.
The association said it recognizes the benefits that union power can bring to family child care providers, but that SEIU had used high pressure recruitment tactics in which union officials had misrepresented themselves.
"However, due to SEIU's history and organizing tactics here in Maryland, we do not feel that they are the right union for Maryland's family child care providers," the statement said.