Michael Barrios slid a pass across the box to Rubio, who deftly sent a right-footed shot just inside the left post to open the scoring.
Rubio's goal was his third in his last four matches and team-leading 15th of the season. He moved within one of Conor Casey's franchise record for goals in a single season, set in 2009.
William Yarbrough finished with one save to record his ninth clean sheet of the season for the Rapids (11-13-9, 42 points), who improved to 5-0-4 in their last nine home matches against FC Dallas. Their last loss at home to FC Dallas was a 1-0 decision on Oct. 18, 2014.
Colorado played a man down after defender Gustavo Vallecilla received a red card in the 77th minute.
Rapids defender Drew Moor received a strong ovation from the home crowd upon entering the match in the 80th minute. Moor, 38, announced Friday that he planned to retire from professional soccer after the season.
Maarten Paes made five saves for FC Dallas (13-9-11, 50 points), who saw their four-match unbeaten streak (2-0-2) come to a halt.
A sterling kick save along the goal line by Rapids defender Keegan Rosenberry kept the match scoreless in the 23rd minute.
FC Dallas' Jader Rafael Obrian evaded the charge of Yarbrough and regained possession of the ball in a prime scoring area. He immediately sent a shot toward the net that was denied by the extended right foot of Rosenberry.
FC Dallas nearly dented the scoreboard in the 52nd minute, however Jesus Ferreira's shot from just outside the box caromed off the left elbow of the crossbar. Ferreria, who has scored a franchise high-tying 18 goals this season, tallied twice in FC Dallas' 3-1 win over Colorado on April 9.