Can a preacher answer God's calling without being a good public speaker?

I ran across the religion channel the other day and began to listen to a preacher. He was talking about Peter this and Peter that at the time. I started wondering if just anyone could be a preacher or is having good public speaking skills a pre-requisite?

The definition of preach is 1) to deliver a sermon and 2) to speak or argue in favor of. So even according to the definition, you cannot preach without speaking. Hence, you must have good public speaking skills to even get into the field of preaching.

I wonder if there is some assistant manager working at McDonalds somewhere saying, "If only I had good public speaking skills. I could have followed my dream of being a preacher." Food for thought anyway.