Operatic Versus Normal Voice in A Thousand Miles, by Vanessa Carlton
The chorus is:
If I could fall | into the sky
do you think time | would pass me by?
cause you know I'd walk a 1000 miles
if I could just see you | tonight.
The first two times through this chorus establish the pattern. It begins with normal voice. Carlton then switches to an operatic voice, on or around "I'd" of the third line. This peaks on "1000 miles". The operatic voice is held until about "see" of the fourth line. There is a continuing falling off, so by the time she gets to "tonight", her voice is almost a little breathy.
The contrast isn't as obvious as it might be. First, some singers have a stronger contrast between normal and operatic voice. (Presley's contrast is much stronger.) Second, Carlton does not seem concerned to make her transitions suddenly or consistently. But the basic pattern is always there.
The most cliche use of contrast is to augment the grand finale to a song. Elvis Presley's "It's Now or Never" is a good example. Carlton seems to be doing that in this chorus, but then she "surprises" us and returns to a normal voice, creating a very different mood for the ending. So her use of contrast is both understandable and unpredictable.
The last time this chorus is sung, it is the same up to the next-to-last word -- she starts in a normal voice, moves to operatic on "I'd", and shifts back to normal on "see" and starts "you" with a normal voice. Then, after this note has started in a normal voice, she shifts to operatic voice and extends the note. This is indeed the grand finale.
She doesn't sing the last word, "tonight". Instead, she adds an embellishment to you at the end and then restarts the chorus. Now she sings the chorus from the start in her operatic voice. It contains predictable grand-finale changes in the melody.
But it is not a grand finale. She returns to normal on or about "see". Then it tails off, even into a breathy voice. She inserts a new phrase, so the last line is
if I could just see you | if I could just hold you | tonight.
When she is done, we see that the ending has followed the same pattern as the first three singings of the chorus -- transition to operatic voice, but on a grander scale.