Alright, so maybe it is just by chance that the two names sound a little bit alike. That is, until you consider the fact that Haggerty first 'thought up' the name when he was a 17-year old Seattle high school student. That's right around the time that McLemore brought his talents to Seattle, playing with the Mariners from 2000-2003.
And to add on to that, Macklemore is an admitted baseball fan. He even mentions his respect for former Mariners broadcaster Dave Niehaus in one of his songs, 'My Oh My,' which he performed at the Mariners' home opener in 2011. What he doesn't admit, though, is that he was consciously influenced to dub a stage name based on McLemore's name. At least he does know that it could've been a subconscious thing though (as he has told ESPN.com) because I'm totally leaning towards the fact that it was. I mean, Macklemore is responsible for the recent jam 'Thrift Shop' so it could just be in his nature to recover things and give them new life (HA, get it). That's just speculation, though. Either way, this just goes to show that whether you know it or not, once baseball is in you - it's in you.