Byline: STEPHEN COLLINSON Agence France-Presse
WASHINGTON - Hillary Clinton's 2008 White House foes have more than her opinion poll lead to worry about: Looming just off stage is her election-winning, money-spinning, wild card - her husband, Bill.
Six years removed from power, the former president is back, itching for a fight, but carefully road-testing his role in his wife's bid to become the second Clinton, and first woman, behind the Oval Office desk.
How Clinton and his turbulent and scandal-laced, yet peaceful and prosperous two White House terms, will gel with Hillary Clinton's aspirations, is one of the key unanswered questions of the 2008 presidential race.
"It is a delicate balancing act," said Bruce Buchanan, a professor of government at the University of Texas at Austin.
"The question is, how to use him, without triggering the wrong impressions," said Buchanan, saying Clinton could be highly effective in a nominating process dominated by committed core Democrats.
"Later on, they will have to reconfigure what to do with him should they get to a general election," he said.
A subplot will play out as Clinton's top Democratic rivals Barack Obama and John Edwards implicitly reference less savory parts of the ex-president's legacy and probe the grass roots for any signs of Clinton fatigue.
Bill Clinton is still a hero to many Democratic Party faithful, and has lost none of the campaigning skills which made him the first Democrat since Franklin D. Roosevelt to win two terms and drove a generation of Republicans to distraction.
But the Clinton camp must ensure the former president's dazzling stage presence does not overshadow his wife's more prosaic campaigning skills.
And those Democrats who still feel let down by Clinton's impeachment over an affair with a White House intern, may find the freshness offered by Obama compelling.
Last week, the former president dipped a toe in the race with a syrupy Internet video tribute to his wife, who he said was the "best combination of mind and heart and leadership ability."
"There are a lot of things about Hillary ... you may not know," Clinton said before highlighting his wife's resumA[c] as an advocate for children, campaigner on health care, and as a face of America in the world as First Lady. …