I though some federal judge threw one of the suits against McCain out say precisely that voters didn’t have standing. I’m probably wrong though.
No. You are probably correct.
The question of whether or not a particular plaintiff has "standing" to assert a claim for relief in Federal Court is a technical one usually encompassing several distinct issues.
One is the question of the specificity of the harm suffered by the plaintiff as distinguished from the general populace and the question of whether the plaintiff's harm is directly related to some specific legal requirement.
Another issue is whether the case presents a present controversy. The general argument that the plaintiff would be injured because he would not have a person eligible to hold office under Article II, Sec. 1, Par. 4 of the Constitution is not a present controversy with respect to Obama because Obama might not be elected.
At some point, the argument that there are only two practical candidates of the two record parties, both of whom are not eligible to act under Article II, Sec. 1 might result in a true controversy. However Berg didn't plead that so the argument is not before the court.
At some point, there may well be parties who do have an interest. It seems to me that any Secretary of State (of an individual state) who choose to do so might refuse to certify the electors designated by either or both candidates pending a legal resolution of their eligibility to serve.
Pennsylvania might be an ideal jurisdiction for this argument as might Michigan, Minnesota, or Wisconsin because those states are places which both parties perceive to be keys to the general election. If all four Secretaries of State refused to certify ballots for electors designated for both candidates pending such a determination, likely we would get court involvement.