US First Lady Michelle Obama quickly snapped up tens of thousands of Twitter followers Thursday, as she joined the social network and opened a new front in her husband\'s reelection campaign. \"Hi, everyone, and thanks for the warm welcome. Look forward to staying in touch with you here,\" @michelleobama said in a tweet authenticated by her initials \"mo.\" The account will be mostly run by Obama\'s 2012 reelection campaign, and is similar to @BarackObama\'s Twitter output, which is also mostly a product of campaign staff. Occasionally, however, the president, who is often pictured with a BlackBerry or iPad, does produce a personal tweet, designated by his initials \"bo.\" By late Thursday, hours after the account\'s debut, @MichelleObama had garnered more than 160,000 followers on the micro-blogging site, an impressive total, but well short of her husband\'s following which is close to 12 million. The First Lady also issued another personal tweet, calling on Americans to join her in a day of service for Martin Luther King Day on Monday.