Well worked team goals finished off by Luis Gil (15) and Joao Plata (15) put Real two up before Darlington Nagbe pulled one back on the half-hour, but hopes of a Portland comeback were hit when Ben Zemanski was sent off for a sliding challenge on the stroke of half-time.
Morales took advantage, finishing in spectacular fashion from a 55th-minute corner, and Alvaro Saborio (67) added a fourth, before Sal Zizzo pulled one back 12 minutes from the end.
The result put Real eight clear of the Los Angeles Galaxy in the Western COnference and seven clear of the Montreal Impact in the Shield standings, albeit having played more games.
Andrew Wiedeman's goal in first-half stoppage time ensured the points were shared in a 1-1 draw between Toronto FC and the New England Revolution.
Diego Fagundez had put the Revolution ahead from close range in just the second minute, but Wiedman poked home after a scramble in the penalty area to level just before half-time.