With the deadline to sign up for healthcare under the federal Affordable Care Act at 12 a.m. Tuesday, the federal healthcare exchange Healthcare.gov experienced technical difficulties Monday and was shut down for four hours, according to the Associated Press.

The high volume of traffic on the exchange caused the technical issues as the site recorded a total of 1.2 million visitors by noon Monday. Last Thursday, there were a total of six million individuals signed up for the national healthcare coverage exchange.

Nearly 77,000 Wisconsin residents will be removed from BadgerCare coverage with the open enrollment deadline Tuesday, as the Legislature voted not to expand BadgerCare coverage last year. Those residents will need to seek out private coverage in the federal exchange, where they will qualify for subsidies, to meet federal requirements.

“This historic day when the right to guaranteed health coverage is advancing all overthe country is marred here in Wisconsin by Gov.Walker’s action to force tens of thousands of our most hard pressed working families off affordable coverage,” Robert Kraig, executive director for Citizen Action of Wisconsin, said in a statement.

Gov. Scott Walker has said he rejected the state’s Medicaid expansion because of uncertainty over whether the federal government would fulfill its funding promises, potentially leaving the state to pick up the tab for the enrollment expansion. Walker also crafted an alternative plan that ended the waiting list for childless adults below the poverty level into BadgerCare, shifting those in BadgerCare who were above the poverty level to private plans in the Obamacare marketplace.

Those previously uninsured Wisconsinites will be able to enroll in BadgerCare as of today.

The Associated Press also reported enrollment assistance workers had braced themselves for a potentially large number of applications at job centers across the state.

To deal with the high demand for federal plans, the marketplace began transferring individuals to a virtual waiting room to manage the traffic. It allowed applicants to browse plans in their areas, calculate costs and offered email notifications when the application process was available.

Those who do not have coverage after Tuesday’s deadline will be required to pay penalties on their 2014 federal tax returns, although the federal government has announced some flexibilities on the deadline.