Trending topics are the most-talked-about topics on Twitter at a given time. They are listed on each Twitter user’s homepage to show what topics are currently the most discussed by other users around the city, state, nation or world.

2012 was a big year for Twitter when it comes to politics, and political conversations many times throughout the year seemed to dominate the list of trending topics. The October 2nd Presidential debate between Barack Obama and Mitt Romney made a particularly big splash. “Tonight’s debate was the most tweeted about event in US political history,” a representative from Twitter said in a statement, “topping the numbers from the RNC and DNC.”

According to official estimates, which you can see in the chart below, users ultimately sent an astonishing 10.3 million tweets during the 90-minute debate.

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Later in the year, this became the most Retweeted post of all time:

Four more years. twitter.com/BarackObama/st…

— Barack Obama (@BarackObama) November 7, 2012

But the most notable takeaway from Twitter’s historic year in politics is that conservatives dominated the conversation. Seven of the top ten political trends from 2012 were conservative or Republican-related hashtags or words.

For the uninitiated, hashtags are used to group together conversations on Twitter. For instance, the hashtag #tcot, which happens to have been the year’s top political trend, stands for “true conservatives on twitter.” Conservatives use the #tcot hashtag when sharing their opinions so that other conservative users can find them.

While the Obama campaign’s new media efforts have received a ton of praise (deservingly) over the last several years, it’s clear that the conservative grassroots movement has actually been more engaged on Twitter than their liberal counterparts. Future conservative candidates and causes will benefit greatly if they can find a way to tap into the conservative grassroots online the way the President successfully did with liberals the past two election cycles.