The problem is that the bible does not say what you are saying. It says who so ever speaks a word against the Spirit. It even gives an example of what is meant.
In the NIV Compact Dictionary of the Bible....... It says : Blasphemy is the unpardonable sin referring to basphemy against the Holy Spirit.( Matt 12 :31; Mark 3:28-29 ; Luke 12 :10 ) There is much difference of opinion as to the meaning of this sin, but one of the most popular and likely views is that the sin involves decisively and finally rejecting the testimony of the Holy Spirit regarding the person and work of Jesus Christ.
So in essence I would stick to the theory that any one who rejects the Lord Jesus Christ as his personal Saviour is catagorized in that group who are blaspheners of the Holy Spirit.
That is why it is up to us to get the gospel to the unsaved as there is not much time left before the coming of our Lord.