When such petition demands an amendment to a charter, the chief executive officer shall submit such amendment to the qualified electors of said municipal corporation at the next election of any officers of said corporation and if, at said election, a majority of said electors voting thereon shall vote for such amendment, the same shall thereupon become an amendment to and a part of said charter, when approved by the Governor and filed in the same manner and form as an original charter is required by the provisions of this article to be approved and filed.