As long as the ID requirements are made without regard to race, ethnicity, religion, gender and so forth I do not see how it could be considered bigotry. It seems obvious to me that there is no inherent bigotry to such a thing. Almost anything could be bigotry in certain circumstances. For instance, if a restaurant only carded 25-year-old-looking non-white people but let white people who look 25 drink uncarded, that would be obvious racism.
In another topic, Nick_A and I pretty much agreed on the whole presidential ID requirements thing so I won't get much into that. What I will say is that I do not see how it could be considered bigotry to require all presidential candidates to provide some sort of certain documentation in a certain way of eligibility, namely of having been born in the USA. Of course, there is no doubt to the fact that a good portion of Obama-opponents are racist and have racist motivations for almost any issue they have with Obama and probably go at the issue in a racist way since they are racists. (For instance, consider that most Mississippi Republicans oppose interracial marriage so much that they want it to be legally banned. I don't to detract from the topic, but I think that shows that a large portion of people are racist regardless of how they feel about ID requirements and thus it would be expected that they would support racist ID-requirement inequalities, particularly if it is a mainly republican proposal or talking-point in question.) Nonetheless, to brush off all people who support a certain ID requirement as racist is a hasty generalization fallacy and to brush off the ID issue itself by the (IMO false) belief that all of its supports are racist is clearly an ad hominem fallacy.