40 % of white voters say they 'll vote for President Obama -- the minimum threshold he needs to win . Comment: Political experts attribute lower white support to party identification trends , economy , social policy , race . Granderson : Both parties have a huge race problem . Obama must hold the line with white voters ; get high minority turnout to win .
40 % of white voters say they 'll vote for President Obama -- the minimum threshold he needs to win . Comment: Political experts attribute lower white support to party identification trends , economy , social policy , race . Obama must hold the line with white voters ; get high minority turnout to win .