Final answer:
The media's coverage of electoral candidates has become more focused on analysis rather than reporting. Candidates' use of social media allows for direct communication with the public.
Step-by-step explanation:
The media has contributed to candidate-centered presidential campaigns in two main ways. Firstly, the media's coverage of electoral candidates has become more focused on analysis rather than reporting, with shorter sound bites and horse-race coverage. This forces voters to seek information from other sources, like social media. Secondly, the media plays a strong role in influencing who becomes the Democratic and Republican nominees by discussing candidates' messages, vetting their credentials, carrying sound bites of speeches, and conducting interviews.
Presidential candidates' use of the media has also contributed to candidate-centered campaigns in two ways. Firstly, candidates try to control journalists by limiting interviews and quotes, leading to shallow coverage. In an effort to regain control, journalists analyze campaigns without input from candidates. Secondly, candidates' use of social media, like President Trump's active tweeting, has allowed them to have direct communication with the public and bypass traditional media channels.