Currently Online 
Of Course they can, Xbox is a brand just like Nintendo and Sony and Sega etc. There are no advantages that favour any of them, if anything Xbox has a huge advantage since they are under one of the most wealthiest corporations in the world.
If Xbox really wanted to win the console market they would just sell X1s for $50 world wide, they can afford to do that (they wont because that wont look good on the shareholders) but if they really wanted to they can. This is why gamers need to stop looking at Sales charts. Consoles can sell more based off many things and quality of the product isn't included. They can sell by Bundles, Price Cuts, manufacturing issues, Blu Ray Drives, and simple advertisements.
It makes me laugh when a gamer comes to me talking about "This console is the best because of its sales" when I look at them thinking, there's another suckered in by the marketing. No one seems to care that the Wii dominated the competition last generation because of my points above, Cheaper, bundles, advertisings can lead to winning a console war not games. Lucky for Nintendo's Wii they covered all bases including games.
Lets be honest here when we look at the PS4 and XB1
Ryse - The Order
DriveClub - Forza Horizon 2
Killzone SF - Halo MCC
Bloodbourn - Dead Rising 3
Infamous - Sunset Overdrive
Knack - Ori and the Blind Forest
TLOU-RM - State of Decay-RM
Little Big Planet - Project Spark
Street Fighter V - Killer Instinct
Uncharted 4 - Rise of the Tomb Raider
God of War 4 - Gears of War 4
and many more to come etc.
I haven't put them in the best order but that's only but lets take a good look at that list and can you see a clear winner? Both have better games then the other, Where PS4 has the better Horror game, XB1 has the better Racing game etc
There isn't that much of a difference in terms of quality between the two to justify a superior console and to say one is selling better then the other based off its own library of games. There both equal when it comes to the games, I tip my hat off at Sony for there great marketing because honestly that's all it takes these days to sell consoles. With the change of CEOs at Xbox, they will learn from this and only become better for it with there next effort.
PS3 had a slow start last gen and even out at the end of the generation, XB1 is having a slow start this generation and will most likely end on the same note as PS4.
Gamers need to rejoice and stop hating on other systems. I am a PC gamer and to see people talk down at one another is just sad and gives gaming a bad name. If the 360 didnt do what it did to the PS3 last gen, do you think the PS4 would be what it is today? No.
