Perhaps it was a reference to the overall umbrella of topics that Lehrer defined at the outset, but I don't remember his specific words. I remember my reaction to Kerry's response at the time was "How does he know that?"
KERRY: I know I can do a better job in Iraq. I have a plan to have a summit with all of the allies, something this president has not yet achieved, not yet been able to do to bring people to the table.
We can do a better job of training the Iraqi forces to defend themselves, and I know that we can do a better job of preparing for elections.
All of these, and especially homeland security, which we'll talk about a little bit later.
(then later)
LEHRER: Ninety-second response, Mr. President.
BUSH: I don't think we want to get to how he's going to pay for all these promises. It's like a huge tax gap. Anyway, that's for another debate.
http://www.washingtonpost.com/wp-srv/politics/debatereferee/debate_0930.html