Text of Article 1, Section 4, Clause 1 of the US Constitution with the latter part of the sentence, following the only Semi-colon in the text, is highlighted. To wit: Section 4 The Times, Places and Manner of holding Elections for Senators and Representatives, shall be prescribed in each State by the Legislature thereof; but the Congress may at any time by Law make or alter such Regulations, except as to the Places of chusing Senators.
Of course, the very next portion of that section looks like this, which only means that CONGRESS ALSO has a say in Elections and how they work, if they choose to pass a US Law to do so, except as to WHERE anyone votes for their US Senators.
But presidents? #ZERO power or authority