Thanks for your response,
The pilot flame is blue, and seems to stay in place. The thermocouple does not glow red when the lighting button is down, however when the pilot does stay lit, and the burner kicks on, the thermocouple will glow red.
I was able to light the pilot this morning and ignite the main burner, which stayed on for only 15 minutes or so, before everyting went out. I was able to do this only by holding the lighting button down for several minutes. I tried lighting it again, in the same manner, but the pilot would not stay on by itself.
By the way, where should I look for an air intake problem? Is there some filter somewhere I can clean out?