Because so many Republicans want to be president — or at least pretend they do — debate organizers have decided to eliminate the least popular from the stage based on how they rank in the latest national polls. Fox News, which is hosting the first televised debate Aug. 6, and CNN, host of the second Sept. 16, have come up with a way to limit the field. Basically, it’s the popularity contest presidential elections have always been, only this time there’s no attempt to masquerade it as something loftier.