Remove blank spaces and make lower case

This formula text field removes up to four embedded spaces. You can understand the logic and add more Part() function terms if your strings have more spaces embedded.

Lower(
Left([Field to fix]," ")&Part([Field to fix],2," ")&Part([Field to fix],3," ")&Part([Field to fix],4," ")
)

I was looking for something similar and figured I'd post what worked for me. I used SearchAndReplace combined with Upper in my situation but you can use Lower.

SearchAndReplace(Lower([Field A]), " ", "")

Doing it this way does not require multiple Parts.

Here is the function reference I used.