Just like with Todd Helton, the fact that there are already two first basemen on the bench could stand against the Washington Nationals' first baseman.
However, Morse is more versatile than Helton, so I think that he has more value.
He is also having a career year. His batting average is at .299 and he has almost as many home runs, 15, this season as he has hit in the rest of his career (21 before this year).
Victorino will defeat him first and foremost because the Phillies have many more fans than the Nationals, so the popularity contest aspect will help here.
This is not to say that Victorino does not deserve to beat Morse. Again, he has more runs (53 against 35) and more stolen bases (13 against two). However, Victorino also has a higher on-base plus slugging percentage (.900 versus .887).
As far as sabermetrics go, Victorino blows him away with a Wins above Replacement value of 4.4 as opposed to Morse's value of 1.6 according to FanGraphs.
I think that Morse will be more competition than Helton, but I think that Victorino is more deserving of a spot.