Barack Obama and John Edwards have adopted a risky campaign strategy: Portray Hillary Clinton as no different from President Bush. Yes, it's official: They have gone negative.

Likening Clinton (D., N.Y.) to Bush -- in particular criticizing her for secrecy about her years as first lady -- is a stretch that could backfire. For starters, Democratic voters might not buy the idea that Clinton shares qualities with Bush. This approach also reinforces Republican talking points, which would be a tactical error.

Moreover, if the past is a guide to the future, both Edwards (D., N.C.) and Obama (D., Ill.) had better clear up questions about their own pasts before railing on Clinton's.

Clinton admitted yesterday that her most recent debate performance wasn't "her best." But a

USA Today/Gallup poll released today shows it hasn't affected her position in the race.

After the debate, Obama announced his concerns about Clinton:

After the most secretive administration in memory, an administration that consistently misled the American people, we need a president who is going to be open and forthright. ... Her big answer on whether she would release the papers from her White House years was particularly troubling because she is running on her record as first lady as much as on her record as a senator.

I assume Obama is referring to incidents like the Bush administration's attempt to hide the involvement of big oil companies with Vice President Dick Cheney's energy task force in 2001.

Exxon Mobil

(XOM) - Get Report

,

Conoco

(COP) - Get Report

,

Shell

(RDS.A)

and

BP

(BP) - Get Report

all denied taking part in it, but four years later

documents demonstrated they had. The administration used executive privilege to shield them from revealing the information.

I would think that if Clinton's history is meaningful, then so is Obama's. I pointed out in a previous article that Obama has had conflicts with the energy industry, as was evident when he voted for a pork-laden

2005 Energy bill. He similarly

worked with lobbyists to help two foreign firms with offices in his district:

NuFarm

, an Australian chemical company, and Astellas Pharma, a Japanese drug company.

Obama wants Clinton to reveal her past, but his remains murky. He boasts that he has a longer history in elected office than Clinton or Edwards. Yet

Lynn Sweet of the

Chicago Sun-Times

notes a litany of things Obama hasn't done himself: Nowhere can his records of his time in the Illinois Senate be found; he hasn't disclosed his earmarks prior to 2006; he hasn't made it clear who his biggest campaign donation bundlers are; and he's claimed he would announce all of his meetings as president, even though he failed to do this as a U.S. senator.

Edwards went negative on Clinton long before Obama, questioning Clinton's integrity and her role as a Washington insider. Edwards' campaign has made statements like: "After seven years of George Bush, the American people deserve better; they deserve the truth." They consistently conflate Bush and Clinton.

Edwards' history, however, hasn't been particularly consistent. In 2004, he notably presented himself as a nice guy and refused to attack his fellow Democrats. I guess that pledge is gone.

Edwards has often chosen not to release information when silence suited his purposes. In the 2004 race, he was one of the few candidates not to disclose his bundlers. More recently, he refused to disclose how much money he was paid by Fortress Investments until required to do so by law. Nor did he come forward with information about the $800,000 he was paid for his book by Rupert Murdoch's publishing house.

Edwards has made

poverty a big issue in the campaign. In 2005, Edwards founded the Center for Promise and Opportunity to study poverty. The center raised $1.3 million dollars that year. A

New York Times

analysis reported that the center benefitted Edwards by reimbursing him for travel and hiring his political staff. Donors had no monetary limits and could remain anonymous, unlike in a presidential campaign.

I'm most surprised by the negativity of the two campaigns before the Iowa caucus, which will be Jan. 3. The negative spats between Howard Dean and Dick Gephardt in 2004 brought their campaigns down just a few weeks before the caucus. Gephardt withdrew after a disastrous finish there, and Dean wasn't far behind after a poor third-place finish and the scream speech.

Obviously Clinton isn't a "perfect" candidate. But it is clear that both the Edwards and Obama campaigns may have made a mistake bringing up the past, rather than focusing on how they offer America a better future.