Yes! No story makes it to the front page unless enough people upvote it on the "new" page. Thus, upvoting a new a story gives you much more editorial influence over the contents of the front page than upvoting a story that has already made it there. (And it takes fewer people to flag away an off-topic story while it's still new.)
Another perspective: By browsing the front page, you're looking at stories that other HN readers find interesting. By reading the "new" page, you have the ability to promote stories that you think are interesting.