During a panel on digital politics at the South by Southwest conference on Saturday, Fox News and Daily Caller contributor Mary Katharine Ham said social media sentiment is a reliable predictor of who will win elections. Ham cited Scott Brown’s victory in Massachusetts in 2010 while noting that fellow Massachusetts politician Mitt Romney has failed to engage voters as aggressively through social media channels even though he leads the GOP primary pack.

Candidates, Ham said, use social media to build a brand — implying that the Romney brand has been compromised by his failed efforts to reach voters. She credited the Obama campaign for its adept engagement with social media users.

Moderating the panel was Christina Bellantoni, the new political editor of “NewsHour” on PBS. After the panel concluded, Bellantoni said while Romney’s big money has made him influential, Texas Rep. Ron Paul has been better at leveraging social media to tell good stories, and attract thousands of small donors in the process.

The slate of speakers also included Craig Newmark of Craigslist fame, Heather Smith of Rock the Vote and Maria Teresa Kumar of Voto Latino.

Bellantoni asked panelists whether voters who use Twitter actually pay attention to political views in the tweets they read.

Kumar said her organization launched online contests and games to encourage young people to participate in the 2010 Census.

Newmark mentioned a forthcoming study that suggests Facebook may be a more engaging social media mechanism than Twitter. But neither, he said, is a substitute for grassroots campaigns.

But Smith said she believes a text message that reminds people to vote on election day this year will be just as effective as a phone call. Door-to-door campaigning, she said, lacks the same appeal for most people.

Ham said she personally reads the Tweets of people who reply to her. She added that she has noticed how engaged teenage African-Americans are on Twitter.

Voters, she insisted, genuinely trust the people they choose to follow on Twitter.

Kumar attributed that engagement to high rates of smartphone use among African-Americans, many of whom are early adopters of new smartphone technology.

While Twitter is relatively new, Newmark said, social media in politics is not.

Martin Luther’s “ninety-five theses” document, he said, was a historical example of social media. The sheer variety of Protestant churches today, he concluded, is one result of Luther’s message taking on a life of its own.

Nearly 500 years later, Newmark mused, his quest to improve government through new technologies won’t stop any time soon.

“A nerd’s gotta do what a nerd’s gotta do,” he said.

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