You may want to read your own link before tossing it out as fact. Then you may want to Google "Obama Trump voters" where you will find an endless stream of articles from NYT, WAPO, etc. Check out what Rasmussen Reports said a month ago: 

"...estimates of the raw number of such Obama-Trump voters range from about 6.7 million to 9.2 million."

My own number of 8 million came from a Democratic congressman saying on MSNBC, correctly stating something along the lines of "We need to stop blaming Russia and figure out we can reach those 8 million Obama voters that voted for Trump." I forget his name, I'll see if I can find it.