I started to make a Grammar Guide quiz with examples of whoever and whomever, but I piled up so many sentences with whomever misused that I decided such a quiz would be useless. All the answers would be whoever.
Here are a few of the sentences:
If you’re thinking the jumbled Republican presidential field does not matter because whomever gets the nomination can’t win – think again. A Republican could well take the White House in 2012. (The pronoun should be whoever because it is the subject of the verb gets.)
But here's a reality check: Whomever is elected on Nov. 8 will be limited by the city's thin finances, said Brian Vargus, a political science professor at Indiana University-Purdue University Indianapolis. (Again, we need the nominative case whoever because the pronoun is the subject of a verb is.)
Authorities are asking for the public's help finding whomever is behind a series of burglaries at a storage facility in Clinton in early October. (The pronoun is the subject of is.)
This last example is a bit more complicated. Although the use of whomever stopped me right away, I had to think about it for a while to be sure.
But whomever it is that the Scots-Irish have become in modern America -- along with all the others that settled in Appalachia -- there is still a rich and distinct Appalachian mountain culture that the Scots-Irish helped to create.
You might think that whomever is the object of the verb have become, but it is a subject complement for the subject it linked by the verb is. You could puzzle it out by substituting words and changing the structure.
I am whoever I think I am.
She can be whoever she wants to become.
I am sure that the ubiquity of whomever is a matter of hypercorrection. Writers are trying hard to get the usage right and end up getting it wrong. My advice to writers and editors who think they need whomever: Check again.