It is hardly the same thing. A person who is “called” to be a teacher may be drawn to teaching Special Ed or kindergartners or high school math prodigies and that person (with or without God’s help) can take steps to enter the appropriate field, needing nothing more than the intellectual capacity and the finances to make it happen. Bush did not claim to be called to public service, but to the particular office of the presidency, requiring not only effort on his part, but the direct action of several millions of other people to make it come true.
Had Bush claimed to have been called to run for the presidency, it would not have merited much comment. Any candidate may perform a service, even when they lose. Claiming to have been called to become the president, in which God needed to move the hearts of thousands of financial sponsors, millions of voters, (and, later, at least five justices), is really outside the norm. It is closer to Oral Roberts’s 900 foot Jesus calling him to build a hospital or die trying. I think Bush is neither as crazy as Roberts nor a charlatan like Roberts, but his claim that God wanted him to be president is both unusual and fear-worthy.