Combine first two ingredients in a large resealable plastic bag. Seal and shake to mix. Add chicken, turning to coat. Refrigerate 30 minutes or more. Remove meat from bag; discard leftover marinade. Grill to desired doneness or until internal temperature reaches 165°.
Cut chicken into 1-inch pieces. Place an olive, a tomato and a piece of chicken onto each toothpick. Continue with remaining ingredients. Makes 12 servings.