The Dallas Cowboys are rolling to a degree that is even surprising owner Jerry Jones thanks to the productivity of DeMarco Murray and Tony Romo.

Their next opponent, the Washington Redskins, isn't even sure who will start at quarterback.

The Cowboys seek a seventh straight win Monday night when they host a Redskins team that will likely give third-stringer Colt McCoy his first start in three years.

Dallas (6-1) is enjoying its longest win streak since a seven-game run in 2007. That has surprised Jones, who called the Cowboys a team with plenty to prove before the season.

"I think our record is above what we could have expected, but we have it and it's a credit to a team that's building in confidence," he said.

Murray is the catalyst, becoming the first running back in league history to start a season with seven straight 100-yard efforts. He leads the NFL with 913 yards and seven rushing touchdowns, gaining 128 yards on 28 carries with a score in last Sunday's 31-21 win over the Giants.

The fourth-year pro has a league-high 187 carries -- 61 more than any other player.

"Teams have geared up to stop the run and even though they've done that we've still been able to continue to run the football and DeMarco's a big part of that," coach Jason Garrett said. "I think he's seeing the holes well, he's feeling the softness well and like he always does, he finishes runs."

The NFL's top rushing attack has made life easier for Romo, who has a league-high 69.2 completion percentage. His passer rating is a career-best 104.7 after he threw for 279 yards and three scores last weekend.

"Obviously we were very productive in the passing game," Garrett said. "We didn't throw it that much but when we threw it I think he was 17 out of 23, averaged over 10 yards an attempt, big-time plays down the field, made a lot of little plays, his pocket presence was outstanding."

Washington (2-5) ended a four-game slide with last Sunday's 19-17 win over Tennessee. McCoy was 11 of 12 for 128 yards and a touchdown in relief of an ineffective Kirk Cousins, who was intercepted for the NFC-worst ninth time.

Coach Jay Gruden has named McCoy the starter Monday, though he also said there is a chance that Robert Griffin III can return from a five-game absence due to an injured left ankle.

"I've already made the decision. I've said it's going to be Colt," Gruden said. "I've said Robert will be the wild card, possibly, if he's ready to go, and that still hasn't been decided yet."

Gruden said Griffin has yet to be cleared for full contact, and that he'd like to see Griffin go through a couple of days of rigorous practice once the OK comes from doctors.

"There's a lot of variances as to whether or not we think he'll be ready for Monday night," the coach said.

McCoy went 6-15 as a starter between 2010-11 with Cleveland. He thinks his experience as a backup the last two years will help him Monday.

"I would say I'm older, maybe a little bit stronger," McCoy said. "I think I've learned from my past experiences and watched a lot of good quarterbacks play and hopefully by doing that you naturally gain a little bit of confidence even though you're standing on the sidelines."

These teams feature explosive receivers. The Cowboys' Dez Bryant enters Week 8 in eighth place in the league with 590 yards and the Redskins' DeSean Jackson is ninth with 528.

Jackson, however, had one receiving touchdown in 10 games against the Cowboys with NFC East rival Philadelphia.

The Redskins could use a boost from Alfred Morris, averaging a career-low 62.9 yards on the ground. The third-year back gained 313 in a sweep of Dallas in 2012 before amassing 168 last year in two defeats.

Washington will be without three-time Pro Bowl linebacker Brian Orakpo, who will miss the rest of the season due to surgery on a torn right pectoral muscle. Rookie second-round pick Trent Murphy will start in Orakpo's spot.

The Redskins have dropped eight straight to NFC East foes for their longest skid in the division since a 15-game slide from 1993-94.