balloting vs write-in

balloting and write-in both are nouns.

Word	Noun	Adjective	Verb	Adverb
balloting	Yes	No	No	No
write-in	Yes	No	No	No

As nouns, write-in is a hyponym of balloting; that is, write-in is a word with a more specific, narrower meaning than balloting:

balloting: a choice that is made by counting the number of people in favor of each alternative
write-in: a vote cast by writing in the name of a candidate who is not listed on the ballot

balloting (noun)	write-in (noun)
a choice that is made by counting the number of people in favor of each alternative	a vote cast by writing in the name of a candidate who is not listed on the ballot
	a candidate for public office whose name does not appear on the ballot and so must be written on the ballot by the voters