Earlier today, an account run by President Obama's 2012 campaign staff, was created for Mrs. O. All tweets written by her will be signed "-mo."
Hours later, the First Lady tweeted her first message saying, "Hi, everyone, and thanks for the warm welcome. Look forward to staying in touch with you here. -mo."
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The account has been live for a few hours and the First Lady already has close to 150,000 followers and counting.
With the announcement, celebrities immediately chimed in to tweet their support for her arrival to the social media site. Comedian Steve Harvey wrote, "Hello everyone! Let's welcome @MichelleObama to Twitter" while media mogul Russell Simmons tweeted "Welcome to Twitter @MichelleObama!"
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But perhaps the most sincere tweet came from her husband, President Obama, who wrote, "It's not every day we get to welcome the First Lady of the United States to Twitter -- happy to have you."
So far, Mrs. Obama is following five accounts -- two of which are very dear to her heart -- President Obama's and Let's Move.