"I cannot tell you the selfish pleasure I get out of working with President Clinton," Bush told the near graduates of the University of New Hampshire. "It's a very selfish feeling I have in my heart that we can be out there transcending politics, doing something to help others."
Clinton returned the compliment.
"Our differences are important; they matter. They make life more interesting and they aid the search for truth," he said, "but our common humanity matters more."
On the eve of the first election since 1928 without a sitting president or vice president in the race, in a state that well may determine the longevity of their shared dynasty -- both presidents spoke of giving back.
President Clinton, who spoke of "seeing" and recognizing ourselves in others, said, "There's nothing beyond the reach of our common endeavor because it's our common endeavor."
"You don't have to be a president to be a leader and to touch the lives of your fellow countrymen," former President Bush said.
"Unless you're Shirley MacLaine," Bush concluded, "you only get one shot at this life," before later adding, "Be bold in your caring, be bold in your dreaming and above all else, always do your best."
ABC News' Liz Marlantes and Quiana Burns contributed to this report.