This amendment will guarentee that the Presidential candidate with the largest number of votes nationally is awarded the presidency. This is to guarantee a fully democratic process for electing the President.
Our forebearers could not have imagined or calculated the sheer magnitude of populations that would result in the apparent contradiction between electoral votes and the popular vote as have occurred in elections of the 21st century. In these elections, up to hundreds of thousands of people voted for the candidate who was awarded the lesser amount of electoral votes. This allows for undemocratic manipulation through gerymandering, voter suppression, uneven application of voter rights laws, etc., and other such practices.