Ever since the kickoff of the Republican National Convention last week, Twitter’s @Gov team has been hard at work monitoring tweet buzz – mostly in the form of total tweets and spikes in tweets per minute.

For instance, last week they told us that there were over 4 million RNC-related tweets over the course of the week – 2 million of them coming on the final night (Mitt Romney, Marco Rubio, and Clint Eastwood generated quite a bit of buzz). In fact, the 2012 RNC generated more tweets before the first keynote speaker stepped up to podium than the 2008 RNC did during the entire convention.

Now, Twitter’s saying that the first night of the Democratic National Convention has already generated over 3 million tweets.

And it’s not just the DNC in general that’s besting the RNC in terms of Twitter buzz. Last night, Michelle Obama saw a spike of 28,003 tweets per minute at the conclusion of her speech. Mitt Romney’s biggest TPM spike during his speech was 14,289 – just barely over half of the First Lady’s.

Other speakers last night included Mayor Julian Castro and Governor Deval Patrick, who scored TPM spikes of 11,5093 and 6,909, respectively. Last week, Senator Marco Rubio saw 8,937 TPM and Ann Romney saw 6,195.

Why so much more buzz for the Democrats than the Republicans? One reason could be that the Democrats tend to be more enthusiastic about social media – especially when it comes to politics. A recent Pew study showed that Democrats are much more likely to use sites like Facebook and Twitter for political purposes, and liberals are more likely to use social networks in general.

[Lead image: President Obama and the first kids watching Michelle Obama’s speech]