The U.S. Senate on Thursday passed a landmark healthcare bill, which will expand healthcare insurance coverage to 94 percent of the Americans and could usher in the biggest change in U.S. healthcare in decades.

The legislation was passed in a rare early morning vote starting 7:00 EST (1200 GMT).

Healthcare reform has been the top priority on President Barack Obama's domestic agenda, but finalizing the details of the healthcare legislation has been a lengthy and complex process.

After its passage, the bill would still have to be reconciled with a more expansive bill passed by the House of Representatives before being sent to Obama for signature, which will not happen until later next month.