The sovereignty of God does not need to be established. As an essential aspect of His being and person, it is in no way contingent. The sovereignty of God does not depend, for either its existence or its manifestation, on either the fact or the mode of election. God is sovereign, regardless of whether He elects, or does not elect... whether He elects some, or all... whether election is conditional or unconditional. Neither the fact of election nor the mode of election nor the extent of election affects the fact of (His) sovereignty..., and the assumption that unconditional particular election is necessary for the preservation of (His) sovereignty... is a theological humbug which for generations has been used by Calvinists to beg the question. (Shank; Elect in the Son, p144)AsI have argued before, just because God can do something, does not mean He is obligated to do it. Just because He could have designated particular individuals for salvation in eternity past (and therefore by corollary, all other particular individuals for damnation without recourse) doesn't mean He did it. Just because He is sovereign over all things, doesn't mean He must exercise that sovereignty.
He could very easily have instructed all people everywhere to seek Him, and then rewarded those who did. And of course, that is exactly what He did (Hebrews 11:6).
He could have promised that all who seek Him with all their hearts would find Him. And that also is what He did.
He could have promised that all who ask will receive, all who seek will find, and to all who knock, the door will be opened. And again, well, ...you know
He could have promised the Holy Spirit, the mark and the agent of regeneration, to anyone who asks Him. And, well I could go on.
Those who insist that because God can do something, He must do it, actually diminish His sovereignty, don't they?