This has confused a lot of people, particularly since the word "he" really is not in the text at all but was simply added by the translators.  Dan 9:27 doesn't really reference the False Messiah, the Real Messiah, or any particular person.  At http://www.fivedoves.com/letters/feb2013/jovial223-1.htm is a very detailed article on this I posted a while back.

Shalom, Joe