If you are ok with the last line always being the same, you could do something really simple like:
<p>bla bla bla blajlkd jflkdj fkljds fökjdkf jölkdj fkljds lkföjkdsl jflkdsj fkjds kföjdsk fj</p>
<p style="text-align:center; margin-top:-1em;>Centered last line</p>