President, first lady mark July 4 with picnic for military families

At an Independence Day celebration at the White House, President Obama paid tribute to the nation's armed services, thanking military members for their service.

"It is always such an honor for us to spend this holiday with members of our military and your extraordinary families," said the president at a picnic for service members and relatives held on the South Lawn.

"All of you represent what is best in America. You serve under our proud flag. You and your families sacrifice more than most of us can ever know — all in defense of those God-given rights that were first put to paper 236 years ago: life, liberty and the pursuit of happiness.

"So as your commander in chief — but also as an American — I want to invite all of you over to say one thing: Thank you."

The president, joined by first lady Michelle Obama, hosted military families for an evening of barbecue, fireworks and a concert by country performer Brad Paisley.

"Today, all across America, at schools and beaches and in town squares, Americans are celebrating the freedoms that all of you and your families defend. Like many of them, we’re grilling in the backyard," joked Obama.

The president, whose campaign has made outreach to military families a priority, also highlighted his administration's foreign-policy achievements in his short speech. 

"Because of your service and sacrifice, we took the fight to al Qaeda and we brought Osama bin Laden to justice. Because of your service and sacrifice, we’re transitioning out of Afghanistan," he said. "We will remain ready for any threat. That is all because of you."

The president also took time to share the individual stories of many service members at the event. 

Earlier in the day, Obama hosted a citizenship ceremony for active-duty immigrant service members, where he honored "some of our newest citizens" and used the opportunity to press lawmakers to take up comprehensive immigration reform. 

After this evening’s picnic, the president will return to the campaign trail, launching a two-day swing through the key battleground states of Ohio and Pennsylvania, with a visit to Toledo, Ohio.

Obama's GOP rival, presumptive nominee Mitt Romney, spent the day in New Hampshire, attending a parade with Sen. Kelly Ayotte (R-N.H.).

Romney also marked the holiday with a video ad thanking service members for their contributions.