Context: Hoping to rebound from their home loss to the Broncos, the Cardinals flew to Monster Park for an NFC West rematch with the San Francisco 49ers.  In the first quarter, the 49ers struck first with kicker Joe Nedney nailing a 49-yard field goal.  Afterwards, the Cards took the lead with kicker Neil Rackers getting a 25-yard field goal and RB Marcel Shipp getting a 5-yard TD run.  In the second quarter, Arizona increased its lead with rookie QB Matt Leinart completing a 6-yard TD pass to WR Larry Fitzgerald, while Rackers kicked a 39-yard field goal.  Afterwards, San Francisco responded with Nedney kicking a 32-yard field goal.  In the third quarter, the 49ers started to retaliate with RB Frank Gore getting a 2-yard TD run for the only score of the period.  In the fourth quarter, the Cards increased its lead with Rackers kicking a 37-yard and a 32-yard field goal.  Even though the Niners would get another score as Gore managed to get a 1-yard TD run, Arizona held on to sweep San Francisco.  With the win, the Cardinals improved to 5-10.

Question: who was leading at end of second quarter?

Answer:
Cardinals