In his letter to Wesley, Whitfield associates Unlimited Atonment with Universal Redemption and rejection of reprobation.
Also, Whitfield believes in unconditional election and that the Gospel is only the means with which election is realized.
However, If the Holy Spirit has to regenerate someone before hearing the Gospel, the Gospel cannot be the means of election, but only incidental to it.
What this would mean is that the person is no longer spiritually dead but yet not in Christ.
He is in some sort of spiritual limbo, neither in the first nor second Adam