Grammar Queen has been on a tear lately at the blatant misuse of the pronouns “whoever” and “whomever.”
Use the same rules that apply to “who” and “whom.”
If the pronoun is the SUBJECT of a verb or verb phrase, use WHO or WHOEVER.
If the pronoun is the OBJECT of a preposition or verb, use WHOM or WHOMEVER.
Examples:
Give assistance to whoever asks for help.
(“Whoever” is the subject of the phrase “whoever asks for help,” which in its entirety–and that is critical!– is the object of the preposition “to.”)
The boss will hire whomever you recommend.
(“Whomever” is the object of the verb “recommend.”)