Shareholders of Amerigroup Corp. on Tuesday overwhelming approved the Virginia company’s $4.9 billion sale to Indianapolis-based health insurer WellPoint Inc.

The vote clears the way for the acquisition to close before the end of the year.

More than 99.9 percent of shares voted Tuesday were in favor of the sale to WellPoint, although those shares represented just 80 percent of all Amerigroup shares outstanding.

Some Amerigroup shareholders had questioned the deal when Amerigroup revealed that a second suitor had been in the mix. A lawsuit filed by two public employee retirement funds accused Amerigroup’s board and its financial adviser, Goldman Sachs & Co., of favoring WellPoint because a quicker deal would trigger a large payment for Goldman.

WellPoint agreed to buy Amerigroup on July 9 to beef up its business of managing Medicaid plans for state governments. The 2010 Patient Protection & Affordable Care Act includes funding to add about 16 million additional Americans to Medicaid plans.