Although the Indians didn't play tonight, their lead in the Wild Card race and defecit in the division race shrunk. The Indians also made up ground on the Boston Red Sox; the Oakland A's beat them tonight. And the White Sox lost again to the Royals.
Why am I mentioning Boston? Because if the Indians catch them, it gives them one more avenue to make the playoffs. After tonight's action, the Yankees trail the Red Sox by only 1.5 games. And the two teams finish the season playing each other. If the AL East is still in play over the final weekend, the first place team can't rest their regulars, meaning the team in the Wild Card race will have a tougher time.
As for the White Sox, I'm still not ready to consider the division in play; 4.5 games is still a a lot to make up in 16 games. But if things go the right way this weekend, the division could absolutely be up for grabs; the White Sox play their next ten games against the Twins and Indians. But at this point, almost everything has to go right for the Indians and wrong for the White Sox for Chicago to lose the division in the last two weeks.
Based on Baseball Prospectus' Postseason Odds, the winner of the AL Wild Card probably isn't going to come from the AL West (~0.5% between OAK and LAA). In fact, there's an 81% chance that the winner of the Wild Card will come from the AL Central.
Regardless of what the odds and standings say, the Indians still need to win ballgames. They may be playing their best baseball of the year (which is saying something), but the Yankees are but a half-game behind.