The fact is KRKO is actually approved for 35kW day, and 50kW with a wicked directional North West, toward Anacortes at night. I doubt you'll get much in Tacoma.
It's a shame really. I have a lot of respect for the station owner. Now that the long battle is almost over for improving the signal on KRKO, albeit not as much as originally hoped, (or were promised), the value of AM stations are going into the tank quick. Younger audiences have no clue that AM radio even exists, and they are the future radio listeners. To top it off, high power AM stations are expensive to operate.
To make matters worse for the future of AM, as I saw first hand at the Consumer Electronics Show this past year, many new auto sound devices don't even have a AM tuner in them. The AM tuner in new cars is being replaced by MS's Sync, Ipod integration, satellite radio, and soon WiMax internet and file delivery.