I live in Northern CA and have made many trips up to Alaska but I always fly into Anchorage and rent a vehicle or RV there. We can fly to Anchorage and use a 25' motorhome (with free mileage) for 30 days for less than the same cost to drive to Anchorage and back.
The only reason to drive would be if I was towing a power boat for use while there or was planning to be there for several months. Even then I would be checking into the cost to ship it all up there and have it waiting for me when I arrived rather than have the $4,000 in fuel costs (plus wear and tear on the RV).