Costco co-founder Jim Sinegal backed President Obama's re-election bid, and on Thursday, Vice President Joseph R. Biden returned the favor.

Mr. Biden took a motorcade to attend the grand opening of the discount retailer's first store in the District of Columbia, located on Market Street in the city's Northeast quadrant. He was greeted by Mr. Sinegal and Costco CEO Craig Jelinek. Mayor Vincent C. Gray and other D.C. officials also attended.