Mitt Romney's presidential campaign is becoming the first in history to buy a national trending topic on Twitter on Thursday, the last night of the Republican National Convention. #RomneyRyan2012, the official hashtag of the campaign, will appear as a trending topic throughout the night.

As of 8:52 p.m. ET, the #RomneyRyan2012 hashtag has seen nearly 10,000 unique tweets (not retweets).

Twitter trending topics start appear on the platform's homepage as hashtags. The company has sold local and national trending topics to businesses since December 2010, and they start at $120,000.

The Romney campaign has also been live tweeting speeches at the Republican National Convention from multiple official accounts in an attempt to create synergy between the online and offline elements of the convention.

"I really think that this convention is achieving what it set out to do, which was to provide a convention without walls," Zac Moffatt, Romney's digital director, recently told Mashable. "I think that we really put an emphasis on being in line with the campaign."

"It's a mistake of the Obama campaign to underestimate us," later added Moffatt. "I hope that's starting to change."

Romney's trending topic purchase was first reported by The Wall Street Journal.

Read more of Mashable's coverage of the Republican National Convention:

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