After the Dallas quarterback caught a virus the night before Thanksgiving, his top two running backs were there to help out.
Romo still did his part. He was behind 7-0 before taking his first snap, and his offense didn't have a yard in the second quarter when he took the field down 21-7 with less than 2 minutes remaining before halftime.
Five completions from Romo later, Murray scored on a 4-yard run 10 seconds before halftime and set the stage for a second-half rally that put the Cowboys (7-5) two games above .500 for the first time since late last season.
Dallas is at least temporarily ahead of Philadelphia (6-5) atop the NFC East.
Greg Jenkins picked up the ball at the 23 after it squirted away from the pile and outran everyone to the pylon. The play was upheld on review after replay showed Williams' knee hitting the turf just as the ball was coming out.
But without much help from the league's fifth-best rushing attack, his offense stalled in the second half as Oakland (4-8) clinched an 11th straight season without a winning record since going to the Super Bowl during the 2002 season.
Murray had just 25 yards after his third TD, but ran for another 38 to help Dallas burn the clock with a seven-point lead in the fourth quarter. Most of the late damage came on a drive to Dan Bailey's 19-yard field goal to put Dallas up by 10 with 1:56 left.
Murray, who tied the score at 7-all on a 2-yard run the first play after a fumble by McGloin late in the first quarter, also had 39 yards receiving.
"I was just playing like I always play," Murray said. "I'm not worried about anything else. I'm just doing the best I can do and trying to help this team win."
Dunbar, who went out with a left knee sprain in the fourth quarter, sparked the tying and go-ahead touchdown drives in the second half, highlighted by a 45-yard run that led to a 4-yard scoring pass from Romo to Dez Bryant, who had seven catches for 61 yards.
McGloin, who was 18 of 30 for 255 yards, converted five straight third downs with passes on a pair of touchdown drives in the second quarter.
He also had a throw to Andre Holmes that was ruled a touchdown on second-and-goal from the 16. After the call was overturned on replay, Jennings scored from the 1 to put Oakland ahead 14-7.
Holmes, who played seven games for Dallas last season before he was sent to the practice squad, had career highs with seven catches for 136 yards. His previous high was 33 yards.
After McGloin completed a 21-yard pass to Holmes on the first play of the second half, the Raiders didn't get another first down until the fourth quarter.
Copyright 2013 by The Associated Press