Commenting about direct election of the president in 1974, political scientist Charles Press wrote that "a most important effect of a straight out popular vote system will be an increased influence of the national media."
If the national media is composed of the news-related cable channels and network television, they have little influence on the presidential elections of this century. Newspapers have even less.
If the national popular vote count determined the president, then more advertising would go to these outlets. In this sense national TV would have increased influence. Currently the networks get almost no presidential campaign ad money. It goes almost entirely to local broadcasters in a few swing states.
A national vote that mattered would cause local newspapers to make more money, potentially a lot more.
But would Fox News and MSNBC have bigger audiences? I doubt it. Would their commentators be more influential? Nope. Would they have editorials? Not likely.
Campaigns would use social media to reach every voter in the country. They would not spend money on broadcast or cable ads in big cities; too expensive. They would pump up ads on local broadcast in all states, local newspapers and radio too.
NYT, WaPo, and WSJ would have to spend more money figuring out what moved voters in every state. They probably would get more subscribers. Local newspapers would surely sell more copies. Interest in local elections would go up. But social media would provide the primary avenue to voters everywhere.