After losing to the Broncos in the season opener, the Colts faced the Philadelphia Eagles in their first home game of the season on Monday night. After a three and out on the Colts' opening possession, the Eagles, led by quarterback Nick Foles, drove down the field and settled for a 31-yard field goal to give them an early 3-0 lead. On their ensuing offensive drive, the Colts drove 72 yards in nine plays and scored on an Andrew Luck touchdown pass to Ahmad Bradshaw, giving the Colts their first lead at 7-3. The Colts extended their lead early in the second quarter on a 46-yard Adam Vinatieri field goal to 10-3. Later in the second quarter, the Eagles closed the gap after a 23-yard field goal from Cody Parkey. The next Colts possession ended in a Luck touchdown pass to Jack Doyle, extending their lead to 17-6 at halftime. The Colts scored on their second offensive possession of the third quarter, with a field goal from Vinatieri, giving the Colts a two possession lead at 20-6. Philadelphia responded on their next drive after driving 80 yards in seven plays and scoring on 1-yard touchdown run from LeSean McCoy, making the score 20-13. After a fumble by running back Trent Richardson on the Colts next offensive possession, set up the Eagles to tie the game on a 19-yard touchdown run from Darren Sproles.  On the first possession of the fourth quarter, the Colts offense drive 80 yards to reclaim the lead on a pass from Luck to Bradshaw and giving the Colts a 27-20 lead. The Colts failed to put away the Eagles, after Luck threw an interception during a play that involved a controversial no-call penalty on the Colts next offensive drive, which set up a five play drive, that allowed the Eagles to tie the game at 27-27. After a three and out on the next Colts possession, the Eagles took possession of the ball at their own forty yard line. Foles and the Eagles offense drove 42 yards to the Colts 18 yard line, with Parkey hitting a 36-yard field goal as time expired, which gave the Eagles the 30-27 victory. With the loss, the Colts dropped to 0-2 for only the third time since 1998.
Question: How many points were the Colts leading by at halftime?
Answer: 9