Fortune has rounded up all of the current thoughts on why the Mac Pro is the only viable candidate:
Earlier this year, after a minor update to the Mac Pro was announced at WWDC, Tim Cook confirmed to a fan that new Mac Pros were coming in 2013, which was later reiterated by an Apple spokesman. The 2013 Mac Pro could be the first to carry the "Made in the USA" label, if current speculation is correct.-A $100 million factory, Dan Luria, a labor economist at Michigan Manufacturing Technology Center told Bloomberg, employs about 200 people and produces about 1 million units per year
-Last year, Apple sold 18 million Macs, including 13.5 million MacBooks and 4.6 million desktops (iMacs, minis and Mac Pros). Only the Mac Pro and mini sell fewer than 1 million per year, and the Mac Pro is considerably heavier and more expensive to ship
-Apple, through a spokesperson and through Tim Cook himself, has already indicated that it will be producing a new Mac Pro in 2013
-Any extra labor costs associated with manufacturing in the U.S. can be more easily absorbed by a $2,500-$3,800 Mac Pro than by a MacBook or an iMac that sell for $1,000 to $1,300.
-Mac Pros are easier to build and customize than any other Apple product
Article Link: Speculation Targets Mac Pro as First "Made in USA" Mac Product