As for the long form... the Census Bureau gave that up and is using the American Community Survey instead. Unless you're talking the IRS long form...
“I think I see what you mean. The Fourteenth Amendment overrides any common-law foundation for citizenship. I don’t want to throw away birthright citizenship until we can come up with a positive, better solution through the Constitution.”
More precisely, the 14th amendment overrode the Dred Scott decision, a decision which some ‘birthers’ here are curiously using vaguely similar arguments to. the 14th amendment repaired a defect in our laws wherein citizenship was not clearly defined.
there is no common law definition of citizenship. Citizenship is defined in US law by statute and our constitution, as the 14th does define ‘birthright citizenship’.