After a tough loss on the road, the Browns traveled again to take on the Chiefs.  In the first quarter, it was all Chiefs as Ryan Succop nailed 2 field goals from 42 and 35 yards out for leads of 3-0 and 6-0.  In the second quarter, Alex Smith found Anthony Sherman on a 12-yard pass for a 13-0 game.  The Browns finally got on the board when Jason Campbell found Josh Gordon on a 39-yard pass for a 13-7 game.  Though the Chiefs pulled away as Smith found Dexter McCluster on a 28-yard pass for a 20-7 lead.  The Browns wrapped things up with Billy Cundiff's 44-yard field goal giving the Chiefs a 20-10 lead at halftime.  In the third quarter the Browns came within 3 when Campbell found Fozzy Whittaker on a 17-yard pass for a 20-17 game for the only score of the period.  In the fourth quarter, the Chiefs wrapped the scoring up when Succop nailed a 40-yard field goal for the eventual final score of 23-17. With the loss and 3-game losing streak, the Browns dropped to 3-5.
Question: How many points did Kansas City lead by at halftime?
Answer: 10