I know a lot of people like to try and do this - drive from Seward to Denali in one day (or v.v.). Certainly it is possible, but as someone who wants to experience Alaska, stop for scenery or wildlife, etc. it is usually not a very good idea. That doesn't even consider construction, slow RV's or what seems to be a more common occurrence - the Seward Highway being closed for some length of time. There was a manhunt just a week or two ago that closed the highway for a couple of hours. Then just last night the highway was closed for 2 hours due to a fatal accident.
Someone is taking their chances as a tourist trying to "make time" in driving this entire 360+ mile stretch on a two-lane road all in one day. Remember, this is not like driving 6-8 hours on the interstate at home. It is like taking back roads in the lower 48.