Personally, i'd think about knocking the running down a little and incorporate some resistance bodyweight exercises at home. You don't need kit.
Pressups, crunches (other ab exercises) etc.
To an 'extent' the fitter a muscle is the more affinity it has to burn fat from around it. This is not spot-reducing as that has been proven not to work as platypus has said, its a more general calorie burning effect from muscles with naturally less fat around it than others anyway.
Remember resistance/muscular exercise will burn more calories at rest so you've more chance of reducing that pouch.
However, are you talking about stomach fat, or just a sticking out stomach? Differences are quite obvious really. Eating too much in one meal can enlarge your stomach, back/abs muscle imbalance can also lead to the perception of a big stomach as it's pushed forward. I've suffered from this.
If it is just stubborn fat around your stomach, then it's exercise and calorie control imho i'm afraid.