ASHBURN, Va. — No one is surprised that Washington Redskins owner Dan Snyder hates the New York Giants, or that Mike Shanahan hates the debilitating salary cap penalty imposed on his team by the NFL.

And, by now, no one should be surprised that the Redskins are playoff contenders with Robert Griffin III, who not only has his first Monday night win but also managed to reference “Gumby” during the postgame news conference.

There was all sorts of passion on display before, during and after the Redskins’ 17-16 win over the Giants. Snyder was heard using a profane word, as first reported by USA Today, to describe the NFC East rivals while congratulating players and staff in the locker room. Washington’s coaching staff used the cap penalties to motivate the players in the days before the game.

“Win one for the cap” doesn’t quite have the same ring as “Win one for the Gipper,” but players were made aware — through a notice posted on an assistant coach’s door — that New York owner John Mara supported the $36 million penalty assessed to the Redskins over two seasons for excessive spending during the uncapped 2010 year.

Shanahan said he didn’t know if the ploy had an effect on the players, but the coach certainly had an extra edge because of it.

“Yeah, it fires me up,” Shanahan said. “Yeah, sure it does.”

What matters is who won the game, of course, and the Redskins (6-6) are now closing in on first place, tied with the Dallas Cowboys (6-6) and one game behind the Giants (7-5). Washington hosts the Baltimore Ravens (9-3) on Sunday, then finishes with a favorable stretch against the Cleveland Browns (4-8) and Philadelphia Eagles (3-9) before a home season finale against the Cowboys.

“We can’t be complacent,” Shanahan said, “because we don’t have the opportunity to be complacent.”

A month ago, when the record was 3-6, Shanahan was talking about evaluating players for future seasons. Now he sees a winning attitude that perhaps best showed itself when the Redskins were able to put the Giants away by holding the ball for the game’s final four minutes.

“They knew we had to run it. We knew we had to run it,” Shanahan said. “And we were able to get a first down. Those type of things build a lot of confidence.”

The Redskins now lead the NFL in rushing with 167.2 yards per game, and Griffin has a 140 passer rating and nine touchdown passes during the three-game winning streak. He ran for 72 yards Monday night but took another solid hit — because he didn’t want to go out of bounds and stop the clock during the final drive.

“I could feel the typewriters writing when I took that hit,” Griffin said. “People are saying I run too much. ... I was bee-lining toward the sideline and at the last second realized I needed to stay in. Coach called it the ‘Gumby hit,’ because my legs bent like Gumby.”

While Griffin was smiling, Snyder was pumped. His exuberance after victories has been well documented by television cameras in previous seasons, and the sentiment behind the words he expressed about the Giants on Monday night — “I hate those (expletive)” — are echoed regularly in both Philadelphia and Dallas.

But it’s been a while since Snyder has had a chance to celebrate a big win. The Redskins are within reach of their first playoff berth since 2007 and are all but certain to end their four-year stranglehold on last place in the division.

“I think that guys are studying harder, making sure they’re playing harder,” said Griffin, when asked what has made the difference over the last three weeks. “I see it in practice, and it makes a big difference on game day.”