Capitalization

Q. Should “tea party” be capitalized? I cannot find it referenced in CMOS, but I’ve noticed that AP news stories lowercase “tea party,” “tea partiers,” and so forth.

A. Since tea partiers have no official party (no officers, no headquarters, no letterhead), we too lowercase phrases denoting tea parties and their proponents.

[This answer relies on the 17th edition of CMOS (2017) unless otherwise noted.]