US President Barack Obama on Tuesday rekindled his odd couple relationship with Republican rising star Chris Christie, as they high-fived on a New Jersey boardwalk hit by Hurricane Sandy.

Christie, the state governor, welcomed Obama to New Jersey on a trip meant to highlight coastal areas rebuilding and bouncing back from the monster storm last October, as the US summer vacation season gets underway.

Christie was heavily criticized by some Republicans last year over his effusive praise for Obama's role in responding to the storm, which bolstered the president's image days before his election faceoff with Mitt Romney.

"New Jersey is more important, and our citizens' lives are more important, than any kind of politics at all," Christie said Tuesday, as he welcomed Obama.

Before the storm, Christie was one of Republican Romney's prime attack dogs, hammering the president's record and leadership style.

But with his state in crisis, the blunt-spoken governor, a possible 2016 Republican presidential candidate, embraced Obama and was paid back with swift federal help and an open line to the White House.

Though he is unapologetic about courting Obama, and may enjoy a political payoff from being seen to work across political divides, Christie risks a backlash from conservatives who decide the Republican Party's nomination.

The president meanwhile is happy for any chance to change the subject after several weeks being battered by controversies over the raid on the US mission in Benghazi last year and tax authorities who targeted conservative groups.

And with the Internal Revenue Service scandal souring his drive to prove Republicans wrong and portray government as a positive force in American life, Obama is keen to highlight a federal recovery project that worked.

"Seven months ago, I promised you that your country would have your back. I told you we would not quit until the job was done, and I meant it," Obama said.

He also praised Christie for "excellent" work in conjunction with federal authorities in rebuilding from Sandy, but warned that more work needed to be done.

"You are stronger than the storm. After all you have dealt with, all you have been through, the Jersey shore is back -- it is open for business," Obama roared in a campaign-style speech.

"Down the shore, everything's all right," Obama said, picking up a line from "Jersey Girl" which was a hit for local hero Bruce Springsteen and was penned by Tom Waits.

Obama and Christie toured a giant sand sculpture being erected on the beach in Point Pleasant, and then took turns trying to win a stuffed bear by throwing footballs on an attraction called "TouchDown Fever."

Obama missed several times but Christie got the ball through a tire on his first shot, prompting the president to offer him a high-five palm slap.

"That's because he's running for office," Obama said, admiring his host's marksmanship and making a reference to Christie's gubernatorial re-election bid in November in a race in which he is heavily favored.

Sandy tore through the Caribbean before slamming into the eastern United States in late October, killing nearly 300 people in the region and resulting in economic losses of more than $75 billion in the United States alone.

Many people in the storm's path are still rebuilding, and some have yet to return to their homes.