For a tax under this subchapter at a rate that does not exceed one-half of one percent, the election requirement under Section 505.251 is satisfied and another election is not required if the voters of the authorizing municipality approved the imposition of an additional one-half cent sales and use tax at an election held before March 28, 1991, under an ordinance calling the election that:
(1) was published in a newspaper of general circulation in the municipality at least 14 days before the date of the election; and
(2) expressly stated that the election was being held in anticipation of the enactment of enabling and implementing legislation without further elections.