Rex Grossman threw for 291 yards with two touchdowns and two interceptions for Washington (2-0), which beat the New York Giants in its opener last week and has won its first two games for the first time since 2007.
"We feel good about where we're going. We feel we're heading in the right direction," Grossman said. "We have a lot to get better on but at the same time, we feel excited that we're headed in the right direction."
Former Cardinal and D.C-area native Tim Hightower rushed for 96 yards on 20 tries and Roy Helu added for 74 yards on 10 attempts. Helu also caught three balls for 38 yards.
Larry Fitzgerald had a big day in defeat, catching seven passes for 133 yards and a touchdown, while Kevin Kolb threw for 251 yards with two touchdowns and one interception on 17-of-30 passing for Arizona (1-1).
Beanie Wells added 93 yards on the ground and a touchdown for the Cardinals.
"They have guys that can rush the passer and their defense is solid all the way through," Kolb said of the Redskins. "Offensively you can see what they can do once they get the running game going. They're a great team. I wish we would have gotten the win today, to show how good of a team we are, but hopefully we'll see them again."
Trailing 21-13 early in the fourth, Grossman led his offense on a 13-play, 73- yard drive, with the crucial play coming on a gutsy fourth-down call. Facing a 4th-and-3 from the Cardinals 18-yard line, Redskins head coach Mike Shanahan elected to call a pass play and attack rookie cornerback Patrick Peterson. The move paid off as Grossman found Moss in the right back corner of the end zone to make it 21-19. The two point conversion attempt failed.
Washington's defense stepped up on Arizona's next possession and forced a three-and-out and Grossman led the offense on an eight-play, 48-yard drive, which ate up nearly 2 1/2 minutes, allowing Gano to connect on the eventual winning field goal.
Grossman was picked off inside the Arizona five-yard line to end Washington's promising first drive and he was intercepted again late in the first quarter. Richard Marshall returned the second pick 33 yards to the Washington 37 and Kolb needed only two plays to punch the ball into the end zone. He completed a 16-yard pass to Andre Roberts, then finished the quick set with a 21-yard touchdown pass to Jeff King for a 7-0 advantage.
The Redskins then marched 77 yards in 14 plays and capped the 8 1/2-minute drive with a 26-yard chip shot by Gano to make it 7-3. Later in the second, the Redskins grabbed a 10-7 lead with a one-yard touchdown strike from Grossman to Davis.
Washington had a chance to add to the lead with only seconds remaining before halftime, but Gano had a 30-yard field goal attempt blocked by Calais Campbell.
Late in the third quarter, Arizona took a 14-10 lead as Kolb led the offense on a 10-play, 90-yard march, highlighted by a 25-yard sprint by Wells to the Washington 31 and capped by Wells as he punched the ball into the end zone with a two-yard touchdown run.
Gano pulled Washington within 14-13 with a 23-yard field goal early in the fourth, but Arizona needed only 20 seconds to extend the lead again as Fitzgerald hauled in a 73-yard touchdown pass from Kolb.
Washington leads the all-time series 74-44-2...Fitzgerald has 66 career TD catches, tying Roy Green for the most by a Cardinals player...Shanahan is 5-0 in his career against the Cardinals, while Cardinals head coach Ken Whisenhunt dropped to 0-3 against Washington...It was Fitzgerald's 27th career 100-plus receiving yard game.