According to the U.S. State Department, Macau is 95.7% Chinese by race. Of the other 4.3%, 1.7% is Portuguese. I found the people of Macau to be slightly darker skinned than their fellow Chinese in Hong Kong or Guilin. You can tell the difference compared to the many prostitutes in Macau, which I hear are mostly from mainland China.
I have been to Europe three times, Asia four, and lots of places in North America, and I must say that I found Macau people to be the rudest I have ever encountered. Some people say Hong Kong is rude, but Macau is much worse. The manners of the drivers are absolutely atrocious. Why anybody bothers to paint crosswalks in Macau, I have no idea, because no drivers will even slow down for pedestrians in them. Casino dealers will wave their hand and remove the case on the chip rack if you walk by, but that is the only greeting, you will get, if you can call it that. Unlike in the U.S., where there is often a fun banter between player and dealer, in Macau the dealers will rarely say a word. In the nicer hotels and restaurants the staff will be nicer, although it often felt forced to me. Don't dare wander into any of the private junket-run casinos, this may or may not lead to a very harsh rebuke in Cantonese.