It's an anime first but the manga is made to follow it very closely, just due to the release schedule the manga came out first and we had like 5 chapters out before episode 6 aired since it was a monthly manga.
Wow the AN thread for Frontier is plain retarded, also you (and Rah) shouldn't give up hope at this point of the show, the writers wouldn't be doing their job if it was apparent Sheryl was going to win. Think back to say episodes 5-7 of ef (I know your girl lost but you probably thought she had it than yeah?) and 6-9 of True Tears, the eventually winners looked completely fucked at those points. Even Kimikiss say 11-18 looked bad for the winner, go back to KGNE the same thing from the mid point to near end. Now who's in that position in Macross Frontier?