Actually, it appears the statement "Party line vote" is wrong. There are 22 R's vs. 16 D's so 23-15 seems to indicate one dem had a momentary bout of sanity, or he did not get the memo in time.
But there's also the chairman of the committee (a Republican) and the ranking committee member (a Democrat). They get to vote, don't they?
Assuming that they do, there is a total of 23 Repubs and 17 Dems.