06/28/2012 04:09 pm ET Updated Jun 28, 2012

President Obama & FLOTUS Look Happy And Casual At 2012 White House Picnic (PHOTOS)

Today in Washington, something very, very big happened.

But the day before that, President and Mrs. Obama ditched their formal D.C. visages and kept it relaxed for the 2012 White House picnic, held on the South Lawn.

The first couple was on hand to ring in the outdoor festivities, where legislators and their families feasted and played. POTUS remarked that he was "glad to see some folks here in shorts…If you still have your tie on, take it off.” Legislators, their spouses and children mingled with White House aides among tents and scores of picnic tables, and a Marine Corps band played -- wait for it -- country music.

But the best part (for us, at least, since our invitation must have gotten lost in the mail) was that the Obamas were practicing what they were preaching, style-wise. The first lady kept things summery and simple in a green sundress with yellow accents and pointy-toed flats, while Mr. Obama also donned an unusually casual outfit: a blue striped shirt and a pair of khakis.

However, we now have our fashion bummer of the day: Rep. Alan Nunnelee (R-Miss.) was reportedly wearing a seersucker suit, but sadly, we can't seem to find any pictures.

Check out some pics below of the president and Mrs. Obama celebrating a warm summers' night -- before they had something even bigger to celebrate on Thursday.

The Obamas Keep It Casual

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