If the Hawks win their remaining four games, they will most likely make the playoffs as a wildcard. In a way, you could argue that they control their own destiny. Here's why:
If tied with more than one team at 9-7, the first tiebreaker is conference record. The Hawks would be 8-4 versus the NFC and that will get them in.
If tied with the Bears or Giants, the Seahawks have the edge based on head to head records.
If tied with the Falcons for the final spot, the Falcons get in as they beat the Hawks.
A dose of reality: Seattle hasn't one more than two games in a row since 2007. To go 9-7, they would have to win five in a row (and 7 of 8) Not likely.
But who knows?