Whole Foods shareholders have at last voted to advance Amazon's acquisition of the grocery chain, moving the proposal one step closer to reality.

Gathered at Whole Food's headquarters in Austin, Texas, the retailer's shareholders approved a merger with the internet giant on Wednesday morning. Amazon shareholders don't need to sign off on the deal.

Now, completion of the transaction is subject to regulatory approvals and other customary closing conditions. Whole Foods and Amazon are preparing to seal their $13.7 billion deal, which would also mark the biggest retail deal of 2017.

The parties expect to finalize the merger during the second half of 2017. Though, a source familiar with the matter has told CNBC the deal could happen sooner rather than later.

Among many things, this deal will provide Amazon a much more extensive real estate footprint.

Meantime, some analysts and investors worry the deal could upend the landscape for grocers, food delivery services and meal-kit companies. Evidence of this is already playing out with Blue Apron, whose stock has tumbled following an initial public offering earlier this summer.

Just hours after Wednesday's shareholders vote, the Federal Trade Commission said it will allow the Amazon-Whole Foods deal to proceed. The FTC had been conducting an investigation to gauge whether the merger would decrease competition under federal regulations.

Prior to its talks with Amazon, Whole Foods was taking a beating by the Street as its sales slumped and competition in the food-retail marketplace was only intensifying.

Amazon offered to buy the company for $42 per share, which represented a 27 percent premium at the time of the announcement back in June.

—CNBC's Deirdre Bosa contributed to this reporting.