Decision 2012: President Obama Leads Among Independent Voters

Thanks to large leads among women, Hispanics and independents, President Barack Obama leads challenger Mitt Romney 49 percent to 43 percent in the latest NBC News/Wall Street Journal poll. But a six-point advantage is not insurmountable, and Romney is in a strong position to make it a close election.

Class discussion: Take a look at news reports about polls. What is the "margin of error" in polling? How is it determined? Survey results also can vary greatly during a campaign. Can you find examples of dramatic polling shifts during the Republican primary campaign? How accurate were polls in the different primaries?