It is very common for people to misspell words.
One search engine strategy is to buy sponsored links for misspelled words, or to optimize the website for misspellings. Even though only a small percentage of searches may be misspelled, it also may be far easier to get top rankings for the misspelled version.
A client of ours accidentally misspelled a word “Cumaru” (a kind of wood) on their website and got visitors from searchers all over the world who misspelled it the same way they did, “Cumuru”.
The White House website includes misspellings of President Obama’s first and last name.
Another example for your amusement:
Graph of searches for “Khan” with different number of “A”s.