Cover potatoes with water in 4-qt. (4-L) saucepot; bring to a boil over medium-high heat. Reduce heat and simmer 10 minutes or until potatoes are tender. Drain and cool slightly.
Cook bacon in large skillet over medium-high heat until crispy; remove and crumble. Reserve drippings. Add onion to reserved drippings and cook over medium heat, stirring occasionally, until tender. Stir in vinegar, water and sugar. Bring to a boil over high heat. Reduce heat to medium, then add potatoes and chives; toss gently. Cook until liquid is evaporated, about 2 minutes. Remove from heat. Stir in bacon and Hellmann's® Real Mayonnaise. Serve warm.