Jeb Bush, finds himself in the twilight zone of politics. He's hugely popular with the GOP base but Americans may be wary to make him the third Bush to be president among the last four of the country's leaders. One hears conservative politicos wishing that he had a different surname. (What did you say, Jesse?)
Even though America has prided itself on being a meritocracy that objures dynasties, of the 43 presidents, we have had two father/son combos (Adamses & Bushes), one grandfather/grandson set (Harrisons), and 29 (of the 42) cousin/cousin groupings. (N.B. Grover Cleveland was our 22nd and 24th President: ergo, we have had only 42 men serve in that capacity.) Only thirteen, including Reagan, Jackson, and Kennedy, have not have had presidential relatives. Perhaps, Americans can tolerate another Bush.
As for Jeb, he would be probably the strongest choice for Republicans if he had a different last name. The ratings of his brother, W, are in the tank now: however, W's ratings are similar to the nadirs of his seven immediate predecessors. Maybe, he'll can find a way to win in Iraq and/or rally the nation domestically. If so and if Hill (wife of an earlier prez) looms, maybe, America will be amenable to a new first--presidential brothers.
Jeb could bring alot to the table. As a conservative Catholic married to a Mexican lady and a popular past two-term governor of a big state with with an older, Democratic demographic and a significant Hispanic community, Bush has more than a few top cards to play. His strong leadership in natural disasters would be a welcome contrast to those who felt that his brother did not excel in Katrina. Further, his social and conservative credentials would help keep the base.
Cf. http://library.thinkquest.org/TQ0312172/cousins.html and http://www.worldnetdaily.com/news/article.asp?ARTICLE_ID=46832.