This provision is particularly beneficial for low-income earners with very young children, as those individuals may only be able to work part time so that they can care for their kids.
"Right now, the child tax credit starts phasing in at $3,000," said Chuck Marr, director of federal tax policy at the Center on Budget and Policy Priorities, a Washington, D.C. think tank. "[Under the proposal], once you start working, after every dollar of wages earned, you get some of the tax credit."
Clinton has made child care a major focus in her campaign, proposing to cap child care family expenses at 10 percent of annual income.
Though Clinton's announcement didn't specify how much her proposal would cost, her campaign said "it will be fully paid for by her proposals to ensure the wealthy, Wall Street, and big corporations pay their fair share."
The cost is estimated at $150 billion to $200 billion over 10 years, according to a Clinton aide.