Team King of the Hill is like TDM, except the goal is to hold ground. This makes a big difference in strategies. You can let an opponent outscore you 10-1, as long as you keep 1 man in the zone longer than they do. Of course, it's hard to keep a man in the zone if you are being slaughtered, but if they are too busy shooting at everyone except the one critical man, you win.
Learn the best hiding spots in the zone, and try to keep 1-2 people in them, and the firefight going on outside the zone is just a diversion.