CHARLOTTE, N.C. (AP) - Add Dale Earnhardt Jr. to the growing list of car owners searching for sponsorship.

The Navy is leaving the No. 88 Chevrolet in the Nationwide Series at the end of the season, forcing Earnhardt to search for funding for the flagship car at JR Motorsports.

"We were informed last week that our sponsorship with the U.S. Navy will not renew at the end of the year," team spokesman Mike Davis said Tuesday. "It's been an exceptional partnership since 2005, and we look forward to a strong finish to the season as Brad Keselowski and the No. 88 Navy team contends for a NASCAR Nationwide Series championship."

Keselowski gave the Navy its first NASCAR victory last month with a Nationwide win at Milwaukee. He's second in the series standings, and trails Clint Bowyer by 202 points.

The Navy has been sponsor of Earnhardt's first car as a NASCAR owner since the formation of JR Motorsports. Last year, he merged his operation with Hendrick Motorsports and now fields two cars out of his new shop in Mooresville.

The second car, the No. 5, has been driven by multiple drivers and has used multiple sponsors all season. Mark Martin drove that car to Earnhardt's first win as a car owner at Las Vegas in March.

Sponsorship woes are affecting many NASCAR teams in this economic downturn. Just last week, Chip Ganassi shuttered his No. 40 Sprint Cup Series team driven by Dario Franchitti because of a lack of funding.

Several other teams have stopped coming to races — the number of cars that attempted to qualify for Saturday night's Sprint Cup race at Daytona was down eight from the 53 who attempted to make the season-opening Daytona 500. Of those, six lacked full sponsorship.