Hillary Clinton could suspend her campaign after the last primaries are finished (without conceding or endorsing Obama), and still leave herself as a potential choice, if Obama's campaign should flounder.

Recent polls show Obama sagging in popularity among women and white voters in general, since the Rev Wright story broke about 2 months ago. Byron York of the National Review described Obama's campaign as "losing altitude", and that his numbers can't go much lower without his campaign completely losing the ability to win.