For the so called election in HK
Total eligible votes: 795
Total votes cast: 772
Tsang= 649: 84%
if the invalid votes are assumed as for protesting against Tsang, then it would be 18%:82%
Now, if we believe the poll is correct, it is more like 21:62 OR 25%:75%. The margin of error of these surveys are usually only a few percentage point (e.g. 3%).
There is no way the 2 results would overlap.