May Have Chance
On the one hand, the more candidates run, the more ideas and policies are put on display and circulated, which draws in more people, and, the more candidates that run, the more demographic diversity is displayed (subtle identity politicking), which draws in those corresponding demographics.
On the other hand, the more candidates run, the greater the number of disappointed and angry people when those candidates lose, which means increased division, and increased disillusionment, which warps the mind and results in people not voting or voting third party or voting for the Republican candidate.