Nov. 7, 2012 at 1:05 AM ET
Updated 11/7, 8:00 a.m. ET: Minutes after NBC News had projected President Obama to win re-election, he celebrated late Tuesday by sending out a photo with the first lady titled simply, "Four more years." According to Twitter Government, this was the president's most re-tweeted missive ever (as of now, more than 600,000 and counting).
Before he even gave his acceptance speech, he took to Twitter to thank voters directly: