As this is another in the series of playoff posts I've made lately, I thought I would direct you to the last one I made, where you can find each team's upcoming schedule.
With that said, let's be honest here. The Cardinals playoff hopes have diminished somewhat after the Lions and the Falcons have both won. Here are how the teams in the NFC wild card hunt stack up after week 15:
Detroit Lions: 9-5
Atlanta Falcons: 9-5
New York Giants: 7-7
Chicago Bears: 7-7
Seattle Seahawks: 7-7
Arizona Cardinals: 7-7
There are two wild card spots open, but only one of the teams between the Lions and Falcons need to collapse. The Lions face the San Diego Chargers and the Green Bay Packers in the next two weeks. With the Kansas City Chiefs defeating the Packers in week 15, it seems likely that the Packers will use their backups in week 17 while the Lions will have something to play for. The Lions looked exploitable and beatable, but the Raiders couldn't finish them off today. The Falcons face the New Orleans Saints in week 16 (a matchup they are likely to lose), and the Tampa Bay Buccaneers in week 17 (a matchup they will likely win).
Most significantly, the Cardinals face a Cincinnati Bengals team trying to make the playoffs themselves in week 16 and a Seattle Seahawks team trying to do the same in week 17. Though the Cardinals have won a lot lately, these are not easy matchups and are by no means guaranteed wins. But let's assume that they do win both games, and further that the the Lions lose in the next two weeks. In that situation, the playoff picture would (potentially) look like this:
Atlanta Falcons: 10-6
Arizona Cardinals: 9-7
Detroit Lions: 9-7
Seattle Seahawks: 8-8
Chicago Bears: 7-9 (with Caleb Hanie at QB, they can't win any matchup)
The tie breakers in that case work like this:
Arizona would win the second tie breaker by having a 4-3 division record compared to Detroit's 3-3 (if they lost to the Packers).
This is, of course, the optimal scenario. A lot needs to work for the Cardinals to get into the playoffs. Yet...it's still very much possible.