When the mayor is absent from the village, or is unable for any cause to perform his duties, the president pro tempore of the legislative authority shall be acting mayor. In case of the death, resignation, or removal of the mayor, such president pro tempore shall become the mayor and shall hold the office until his successor is elected and qualified. Such successor shall be elected to the office for the unexpired term, at the first regular municipal election that occurs more than forty days after the vacancy has occurred; except that when the unexpired term ends within one year immediately following the date of such election, an election to fill such unexpired term shall not be held and the president of the legislative authority of the city shall hold the office for such unexpired term.