It's a debate on where to stream the presidential debate.
The face-off will be virtually identical on both social networks. But that doesn't mean your experience will be. Which social network should you tune into? That depends on how much you want to throw down yourself.
"Facebook is more akin to being [in] a living room where you have your friends and you have your relatives, it's personal," said Omar Akhtar, an analyst at research firm Altimeter. "Twitter is like the town square. Everyone is loudly proclaiming their opinions, it's out to the public."
Twitter's open platform makes it possible for you to see reactions in real time and search for top comments. Facebook's privacy settings make it hard for public conversations, but friends and family will likely weigh in.
All the way Live
While their approaches may differ, both social networks are using live video to hook users and gain relevancy during marquee moments. Twitter has been packing on shows for its growing network of live streams, including games from Major League Baseball, the National Basketball Association and the National Football League. Facebook has signed deals with hundreds of celebrities and publishers to stream through its Live platform.
Twitter and Facebook both hope to hook political junkies during Trump and Clinton's first presidential debate. The two social networks first faced off at the Democratic and Republican national conventions with competing stream.
Facebook has the advantage on reach, with 1.7 billion active monthly users versus Twitter's 313 million. In their first match-up from the conventions, Facebook, which partnered with ABC News, received 28 million video views. Twitter did not release viewership numbers for its convention streams, part of a partnership with CBS News. (Disclosure: CBS is the parent company of CNET.)
But where Twitter lacks in reach, it makes up for in speed. The social network is known for its live, quick reactions from users during mass media events.
"Twitter may have an advantage here because they have been marketing themselves as a real-time news and information service for many years," said Gartner analyst Brian Blau. "They are in tune with real-time events, I would say a bit more than Facebook."
This year's series of debates could sway undecided voters. Most of the convincing will likely be done on Twitter, where there's more of a free-flow exchange of ideas -- many conflicting.
Facebook users tend to shut out dissenting opinions by surrounding themselves with like-minded voices, Local Search Association analyst Greg Sterling said.
So while Facebook will likely win in terms of reach, Twitter has a better chance at influencing viewers.
"In terms of raw numbers, Facebook wins. But in terms of quality, Twitter offers a more interesting experience," Sterling said.
Content from the streams could be also be a major factor to attract viewers on both social networks.
Facebook will team up with ABC News again, while Twitter will partner with Bloomberg for the debates. Twitter users will be able to watch live either through debates.twitter.com, Twitter Moments or Bloomberg's account @bpolitics.
"As we move further into the election cycle, there continues to be a voracious appetite for live content and we know many users turn to Facebook to engage and participate in the conversation," ABC News's Vice President of Digital Colby Smith said in a statement.
ABC News will be using viewers' comments and questions as part of its coverage on Facebook Live. Bloomberg has also said it would use Twitter's reactions and analysis as part of its broadcast.
"Twitter is where the 2016 presidential election is happening every single day," Anthony Noto, Twitter's chief financial officer said in a statement.
The debates are scheduled for September 26, October 9 and October 19. The vice presidential candidates will also face off on October 4. Where will you be watching?
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