Analysis of Obama's performance vs. polls: Black voters

Recently, Barack Obama has been outperforming polls. The goal of this analysis is to look at how exactly how he is doing this. I will look at pre-election polls that have crosstabs (usually SurveyUSA) with race included vs. actual election exit polls courtesy of CNN. I am going to look at each group independently in different posts, and I am going to separate the analysis into three categories: Pre super Tuesday elections, Super Tuesday elections, and post Super Tuesday elections. I am picking a total of 5 states for this analysis:

• Pre Super Tuesday: South Carolina
• Super Tuesday: California, New Jersey, Missouri
• Post-Super Tuesday: Wisconsin
  

I chose these because they represent a pretty good cross-section of the electorate. I did not analyze any other states, and perhaps the trends could be less or more significant if I had taken a more detailed look at other states. In this post, I'll look exclusively at Black voters.

Black voters
This is supposed to be one of Barack Obama's key constituencies, and it has been through the election so far. The question we should ask here, however is whether his support has solidified with Black voters over the course of the election.

Pre Super Tuesday election: South Carolina
In this pre Super Tuesday marquee matchup, Barack outperformed pre-election polling very slightly by 4%.

• In pre-election polling by SurveyUSA, Barack had a 73% to 18% edge over Hillary amongst likely black voters, for a gap of 55%
  
• In post-election exit polls reported by CNN, Barack won the Black vote 78% to 19% over Hillary, for a gap of 59%
  

Super Tuesday election: New Jersey
In this 2/5 matchup, Barack significantly outperformed pre-election polling by 14%

• In pre-election polling by SurveyUSA, Barack had a 76% to 22% edge over Hillary amongst likely Black voters, for a gap of 54%
  
• In post-election exit polls reported by CNN, Barack won the Black vote 82% to 14% over Hillary, for a gap of 68%
  

Super Tuesday election: Missouri
In this Super Tuesday matchup, Barack significantly outperformed pre-election polling by 17%

• In pre-election polling by SurveyUSA, Barack had a 74% to 22% edge of Hillary with likely Black voters for a gap of 52%
• In post election polls reported by CNN, Barack won the Black vote 84% to 15%, for a gap of 69%
  

Super Tuesday election: California
In this Super Tuesday matchup, Barack significantly outperformed pre-election polling by 13%

• In pre-election polling by SurveyUSA, Barack had a 72% to 25% edge of Hillary with likely Black voters for a gap of 47%
• In post election polls reported by CNN, Barack won the Black vote 78% to 18%, for a gap of 60%
  

Post Super Tuesday election: Wisconsin
In this post Super Tuesday matchup, Barack significantly outperformed pre-election polling by 13%

• In pre-election polling by PPP, Barack had a 72% to 25% edge of Hillary with likely Black voters for a gap of 47%
• In post-election exit polls reported by CNN, Barack won the Black vote 78% to 18%, for a gap of 60%
  

Here's a chart showing the change over time


Latino voters, and White voters will be covered in later blog posts.