By: John F. Harris and Jim VandeHei, May 1, 2008 03:27 PM EST

Thrown off his game by the Rev. Jeremiah Wright uproar, Barack Obama’s strongest answer to Hillary Rodham Clinton is one he won’t give: Senator, do you really want to get in a contest with me over who has more unsavory personal associations?

For all the coverage about the rising heat between Clinton and Obama, this year’s nomination race still is a mild affair by historical standards — restrained by a powerful sense on both sides that there are lots of things they could say but shouldn’t.

There is one theme, however, that runs through not-for-attribution conversations with both sides: Each candidate thinks the other has unmitigated gall.

The Clintons, to hear associates tell it, are more contemptuous than they ever acknowledge publicly about what they believe is Obama’s breathtaking arrogance — the way he blithely dismisses the ideological showdowns and policy achievements of the 1990s as “old politics,” the way he thinks his thin résumé leaves him qualified to lead the country. Lately, the contempt level on the Obama side toward his rivals likewise has been soaring.

More precisely, things that many people around the candidate have always believed about the Clintons — about their trail of controversies, about their style of politics — have in recent weeks seemed much more relevant. That’s made the temptation to say them in a more public fashion more powerful.

A couple weeks ago, we wrote a column about what Clinton would say if she said what she really thought.

Fairness dictates that we take a crack at the other side of the question: What arguments has Obama taken off the table, even though he thinks they are true?

Like the earlier column, sourcing on this one must stay pretty opaque. And like the earlier column, this one is intended as a reflection, not a validation, of the views expressed in a collection of not-for-attribution conversations with political associates about the behind-the-scenes thinking of the Obama camp.

The one line from the what-Clinton-thinks column that most agitated Obama supporters was our assertion that Clinton, for better or worse, was a known commodity. Her “baggage” has already been “rummaged through.”

To which Obama supporters say: Oh yeah?

All manner of Clinton controversies, Obama partisans argue, have not been fully ventilated.

This includes old issues, like Hillary Clinton’s legal career, which includes lots of cases that never got much public attention even during the Whitewater era.

It also includes new ones, like recent stories raising questions about the web of personal and financial associations around Bill Clinton. Since leaving the presidency, he has traveled the globe to exotic places and with sometimes exotic characters, raising money for projects such as his foundation and presidential library and making himself a very wealthy man.

Which gets us back to gall. In the fantasies of some of his high-level supporters, Obama would peel off the tape to say something like this:

You want to talk hypocrisy? How about piously criticizing me for Jeremiah Wright when you have a trail of associations that includes golden oldies like Webb Hubbell? (‘90s flashback: He was one of Hillary Clinton’s legal partners and closest friends, whom she installed in a top Justice Department job before prosecutors sent him to prison.) It also includes modern hits like Frank Giustra. (In case you missed it: There was a January New York Times story, which did not get the attention the reporting deserved, highlighting how this Canadian tycoon and major Bill Clinton benefactor was using his ties to the ex-president to win business with a ruthless dictatorship in Khazakstan.)

Obama has never pressed Clinton to talk about Marc Rich, even though the former fugitive financier who won a controversial pardon from Bill Clinton gave money to her first Senate campaign.

He has never mentioned her brothers, even though Hugh and Tony Rodham once defied Bill Clinton’s own top foreign policy advisers by entering into a strange investment in hazelnuts in the former Soviet republic of Georgia (they later dropped the deal) and Hugh Rodham took large cash payments for trying to broker presidential pardons.

Obama is likewise galled to be lectured by Clinton for not being sufficiently committed to universal health coverage. Why is it, his team asks, that Democrats have done so little to advance a long-time progressive goal for the past 15 years? The answer has everything to do with Hillary Clinton’s misjudgments when she was leading the reform effort in 1993 and 1994.

Most irritating of all to Obama partisans is what they see as her latest pose: that she is selflessly staying in the race despite the long odds against her because of devotion to the Democratic Party and the belief that she is a more appealing general election candidate.

It is an article of faith among most people around Obama that the Clintons were a disaster for the party throughout the 1990s. When Bill Clinton came to town in 1993, Democrats were a congressional majority, with 258 seats in the House. When he left in 2001, they were a minority with 46 fewer seats. There were 30 Democratic governors when he arrived, 21 10 years later.

As for electability, the Obama side believes — for all his trouble winning lower-income whites in recent primaries — that it is ludicrous to believe she is the stronger candidate in the fall.

A recent ABC News/Washington Post poll found nearly 60 percent of voters think Clinton is dishonest. Think about that: Only four in 10 voters do not think she lies when she needs to. A majority hold an unfavorable view of her.

Will those numbers improve if she wins the nomination and Republicans resurrect the scandals, the Bill Clinton sexual affairs and her Bosnia fib with the same intensity they brought to the Wright uproar? Unthinkable.

Now that the Democratic superdelegates are facing their moment of decision in this close race, you might think it would be time for politesse to give way to an unvarnished discussion about both candidates’ real strengths and liabilities.

The Obama side is frustrated with the news media for not carrying more of its argument. His operatives thought a Newsday story looking exhaustively at her legal career — including the revelation that as a young lawyer she attacked the credibility of a 12-year-old rape victim — would provoke a herd of other coverage. It did not happen.

If he really wanted, Obama could generate all the coverage he wanted about Clinton’s past by leveling accusations in his own words. But that is not going to happen.

Politically, he correctly believes that he would be called out as a hypocrite if he practiced the conventional art of attack politics after preaching against it.

And, to view his motives in the best light — a benefit of the doubt extended by his own team — he believes this campaign would also undermine his governing strategy if elected. He has told associates it would be impossible to win support for a progressive agenda unless he assumes the presidency as a uniting figure who can transcend the personality-obsessed brand of combat that has dominated Washington for the past generation.

“I told this to my team, you know, we are starting to sound like the other folks, we are starting to run the same negative stuff,” he told a crowd in North Carolina this week. “It shows that none of us are immune from this kind of politics. But the problem is that it doesn’t help you.”