More and more I've been rejecting the "White/Caucasian" box on forms and entering Other -- Northern European American.
If African American is valid, then so is Northern European American.
I've been called on it a couple of times and have adamantly refused to back down. If Negroid is racist, then Caucasoid is also racist.
I had a neighbor for awhile -- whiter than me -- who routinely entered African American on her forms. She was born in, and was a dual citizen of, the Republic of South Africa. She got into a bunch of arguments with HR people at various jobs over it, but refused to back down.