Remove and discard giblets and neck from hens. Rinse hens under cold water; pat dry. Split each hen in half lengthwise. Trim excess fat.
Heat oil in a large nonstick skillet coated with cooking spray over medium-high heat.
Add hens; cook until hens are lightly browned on both sides, turning occasionally.
Remove hens from pan.
Add leek; saut until tender.
Place leek and hens, meaty sides up, in an 11 x 7-inch baking dish.
Combine tomatoes and next 9 ingredients; pour over hens. Cover and bake at 375 for 20 minutes. Uncover and bake 10 more minutes or until a meat thermometer registers 18