Winning 2 out of every 3 will probably get it done, and is a doable goal. We're 55-53, with 54 left to play. Winning 2 out of every 3 gets us to 91 wins. Just aim to win each series, especially against the Phillies and Braves, and avoid any losing streaks longer than 2 in a row.
We probably won't get it done, because we haven't demonstrated any ability to play consistently good baseball so far, but it is certainly doable if we play like the team we ought to be.