Obama's supporters went after both candidates in his state senator race and had each of them (one an incumbent) disqualified on technicalities. They did not have enough valid signatures on their petitions to get on the ballot. One had 1850 but after the challenges had less than the 750 requirement. Some of their petitioners printed their names rather than signed (as legally required). Obama's lawyers (with his permission), had them disqualified.
Wouldn't it be poetic justice if Obama himself was disqualified on a technicality (not a natural born citizen)!