Candidates tout their lineage in every election. Certainly you know who the President's father is, and grandfather? if you can claim your family is decendant of a Mayflower family or some other historic figure (positive historic figure) wouldn't you want to share that fact? and really who isnt even a little bit curious enough as a youth or young adult to ask these questions of your family, especially the oldest alive relatives?
down south, we hear "fine Christian gentleman" all the time during election season for whatever it actually is supposed to mean or imply. candidates talk about heritage all the time. and if he doesnt update the bio's what will the next leftie/MSM attack look like?
will this help or hurt him? who knows, but people will judge him how he handles the attack.
As for saying one is descended from a famous historic figure... again, I just see that as rather outdated. I don't think the Dames of the Mayflower and DAR is very influential to most voters today, even in the South.
I do know lots of people, especially today, are curious about their heritage, but that doesn't mean someone who isn't is somehow lacking. To me, this whole "his grandfather was Jewish" thing smacks of some kind of 1920s or 1940s throwback. I just don't get the point. I suppose we just have to agree to disagree on this one.