ARLINGTON, Texas — Maybe the Dallas Cowboys are onto something.

Behind rejuvenated quarterback Tony Romo and NFL rushing leader DeMarco Murray, the Cowboys dominated the New Orleans Saints 38-17 Sunday night at AT&T Stadium.

Dallas (3-1) won its third in row to move into a tie with the Philadelphia Eagles atop the NFC East. The Saints, who came to Texas desperate for a win, fell to 1-3 after their sixth consecutive road defeat dating back to last season.

Romo was all point all the night, picking apart defensive coordinator Rob Ryan’s unit with throws all over the field. Romo finished 22-for-29 for 262 yards and three touchdowns, two to second-year receiver Terrance Williams and another to receiver Dez Bryant.

Murray padded his rushing lead with 149 yards on 24 carries, his fourth consecutive game with triple-digit yardage. The fourth-year pro scored in all four games, and he has five touchdowns for the season after reaching the end zone twice against the Saints.

The Cowboys iced the victory on Murray’s 28-yard rumble in the third quarter that increased their lead to 31-3. And for the first time this season, Murray didn’t lose a fumble.

Dallas, at least a fourth of the way through the season, looks like a potential contender in a wide-open division.

“I think what you find is we’re consistently doing the same things each week,” Romo said. “And in the past I don’t know if we were good enough to really do that.”

The 38 points were the most allowed by New Orleans since a 44-38 loss to the Carolina Panthers in the final game of 2012. The Saints beat the Cowboys 49-17 last season.

“We struggled offensively, defensively, kicking game, coaching,” Saints coach Sean Payton said. “There’s not going to be much good to see on this film. We’re 1-3 right now, and that’s how we’re playing.”

While Romo and Murray racked up big numbers, the Dallas defense was just as impressive against the Saints’ normally potent attack.

“It starts with our defense,” Dallas coach Jason Garrett said. “That’s one of the best offenses in the National Football League over the last 10 years or so. They have a great coach, a great system, a Hall of Fame quarterback and a lot of weapons, and I thought our guys really hung in there.”

New Orleans quarterback Drew Brees wasn’t able to stretch the field, instead settling for short throws and short gains in the first half. The Saints’ lack of a running game — Mark Ingram was out — didn’t help.

Brees completed 32 of 44 passes for 340 yards, the large majority coming in the second half. He threw for two touchdowns and was intercepted once. Pro Bowl tight end Jimmy Graham made eight catches for 86 yards and a touchdown, but he lost a third-quarter fumble.

New Orleans turned the ball over three times, a fact Payton lamented.

“We’re not getting it and we’re giving it,” said Payton, whose team trailed 24-0 at halftime. “That’s a recipe for a loss.”

What the Cowboys said:

“You’re always excited, but each week in the NFL is different. Now you go out and lose next week, and it loses all of its luster and good feelings that you had this weekend.” — QB Tony Romo, on reacting to the win.

What the Saints said:

“It’s challenging, it’s disappointing, it’s frustrating, but it’s on all of us right now. It’s on me, it’s on our staff, it’s on the team. Those are some of the things we’ve got to look to get better at. It’s obviously not where you want to be one quarter of the way through the season.” — Coach Sean Payton, on the Saints being 1-3.

What we learned about the Cowboys:

1. The offense appears as potent as advertised before the season. The commitment to run remains in place — running back DeMarco Murray leads the NFL in rushing — and quarterback Tony Romo looks better each week as he gets further away from his back surgery. The Cowboys didn’t even need a big game from Dez Bryant to demolish the Saints, but the wide receiver did score a fourth-quarter touchdown.

2. Maybe this team can contend after all. The NFC East is wide-open and Dallas has an excellent chance to improve to 4-1 with Houston coming to town next week.

–RB DeMarco Murray leads the NFL with 534 rushing yards. He ran for at least 100 yards in four consecutive games to open the season, becoming the fourth back in NFL history to do that. He also scored in all four games, and he has five touchdowns on the season.

–WR Terrance Williams made the most of the extra attention given to teammate Dez Bryant. Williams had the first two-touchdown performance of his two-year career and finished with 77 yards on six receptions. He came into Sunday with eight catches for 102 yards and two touchdowns in three games.

–QB Tony Romo threw for 262 yards on 22-of-29 passes and had his first three-touchdown game of the season. He completed passes to eight receivers and wasn’t intercepted. He also rushed for 20 yards on six carries.

What we learned about the Saints:

1. The inability to throw the deep ball was somewhat masked in the first three games by quarterback Drew Brees’ accuracy on underneath throws and a solid running game. Without much of a running attack against Dallas, the Saints weren’t able to stretch the field. Brees did make some deep throws in the second half, but the game was already out of reach.

2. The Saints continue to struggle outside of the Superdome. New Orleans lost its past six on the road dating back to last season. Traveling to face the Cowboys figured to help, considering the Saints won four straight on Dallas’ home field. However, New Orleans continued to follow the same script of falling behind early, and it couldn’t catch up.

–QB Drew Brees passed for 340 yards, all but 84 coming in the second half. He finished 32-for-44 and two touchdowns, both in the fourth quarter. His first-half interception led to a Dallas touchdown.

–P Thomas Morstead was on the wrong end a fourth-down fake in the fourth quarter with the Saints down 31-17. He couldn’t find anyone open and was tackled for a loss, giving the ball to Dallas on downs. “The play obviously didn’t pan out like we wanted,” he said. “I didn’t feel comfortable throwing the ball.”

–LT Terron Armstead left the game after sustaining a concussion in the first half.