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Social media analysis: Health care remains No. 1 topic ahead of Obama, Romney debate

Crimson Hexagon Inc. and NBCPolitics.com

Social media campaign analysis for Tuesday, Oct. 2. Click the image for the full daily report.

Throughout a summer of political turmoil over the budget, taxes, national security and gaffes, one issue — health care — has consistently defined the presidential campaign as President Barack Obama and former Massachusetts Gov. Mitt Romney head into their first debate Wednesday evening, according to NBCPolitics.com's computer-assisted analysis of more than 3 million comments on Twitter and Facebook.

M. Alex Johnson M. Alex Johnson is a reporter for NBC News. Follow him on Twitter and Facebook.

Every day since June 28 — when the Supreme Court upheld the Patient Protection and Affordable Care Act, which Obama signed into law in 2010 — "Health Care" has been the No. 1 driver of conversation about the president, making up more than a quarter of positive commentary, according to the analysis:

Among negative commenters, "Obamacare" has consistently been the top driver, as well, only occasionally trumped by "Gas Prices":

Taken together, the two categories make up slightly more than 44 percent of all commentary on Obama over the 3+-month period, an emphasis that's easy to see in this visual representation of all election conversation around the president:

For this report, NBCPolitics.com analyzed 3.46 million social media posts using ForSight, a data platform developed by Crimson Hexagon Inc., which many research and business organizations have adopted to gauge public opinion in new media.

More social media analysis from NBCPolitics.com

It isn't the same as a traditional survey, which seeks to reflect national opinion; instead, it's a broad, non-predictive snapshot of what's being said by Americans who follow politics and are active on Facebook, Twitter or both at a particular moment in time, and why they're saying it.

Explainer: Can you scientifically quantify social media opinion?

More than three months after the court's decision, and even as the issue has receded in media coverage, health care is still what they're talking about:

For Romney, the debate may offer an opportunity to more clearly define himself. Over the same 3+-month period, primary drivers of positive conversation have emphasized Romney's personal characteristics over specific issues:

Critics of Romney have also zeroed in on their general perception of him. The leading negative topic — by just 1 percentage point — has been "Women's Issues" (generally access to abortion and equal pay). Right after that come questions about his connection to "real Americans," his convictions and his religion.

Likewise — and in contrast with Obama — the visual representation of all 1.14 million posts about Romney indicates a high interest in whether he can win in November, as opposed to his stands on specific issues:

NBCNews.com will live-stream the debate from Denver at 9 p.m. ET.