No one will blame you if you can’t keep track of the Republican presidential field. It’s huge. If you count declared candidates, prospectives, and announced aspirants, you have 18 people from across the Republican ideological spectrum: Sen. Ted Cruz, Sen. Rand Paul, Sen. Marco Rubio, Sen. Lindsey Graham, Rick Santorum, Gov. Chris Christie, Gov. Bobby Jindal, Gov. John Kasich, Gov. Rick Snyder, Gov. Scott Walker, Jeb Bush, Jim Gilmore, Mike Huckabee, George Pataki, Rick Perry, Ben Carson, Donald Trump, and former Hewlett-Packard CEO Carly Fiorina. The field is so large that news networks have put limits on who can join the debates. Fox News, for example, will invite only candidates who placed in the top 10 of an average of national polls. Likewise, CNN will hold two debates: one for top-tier candidates, and one for the bottom tier. (One possible effect of this? Underdog candidates will pull every stunt they can to get onstage.)
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Beyond “you only live once,” there are other reasons for these candidates—and others like them—to enter the ring. If they perform well enough, they have a chance at joining the ticket as vice president; they could make their way into the administration as a top official (this is my hunch for Graham); or, if they build a genuine following, they could turn their presidential campaign into national leadership.
And then there are the vanity candidates (Trump, Cain, and Gingrich in 2012; Carson, Fiorina, and Trump again for 2016) who are running to build their visibility in the conservative ecosystem. With their campaigns, they can build new audiences and find new venues—a Fox News show or customers for a new book. It’s unseemly, but it’s a part of the process like any other.