If the close contest persists, that probably keeps all four top candidates politically alive for subsequent races in New Hampshire, Nevada and South Carolina next month. That could suggest a more protracted and unpredictable race ahead.
Going back to 1976, any candidate, Democratic or Republican, who didn’t finish first or second in Iowa was a political dead man, even if some didn’t realize it.
The only exception was 1988 when eventual nominees Republican George H.W. Bush and Democrat Michael Dukakis finished a reasonably close third; both, however, were well-positioned to bounce back shortly and win in their neighboring New Hampshire.