Defense lawyers lit into U.S. Rep. Chaka Fattah's hired political gun Thursday in a dogged cross-examination of the man who has emerged as a key witness in the government's racketeering conspiracy case.

It remains to be seen whether their attacks on Thomas Lindenfeld, the chief strategist behind Fattah's failed 2007 mayoral bid, were enough to sway the federal jury weighing the fates of the congressman and his four codefendants.

In six hours of testimony, Lindenfeld parsed words with the smoothness of a man who had spent the last three decades working in Washington politics. He easily dodged questions framed to elicit damaging responses and reframed them so he could give the answers he wanted.

And yet, lawyers for Fattah and the others sought to use that verbal dexterity against him, painting Lindenfeld as a mealymouthed operative willing to say and do anything to win, both in campaigns and in court.

"Is there something about being a political operative that prevents you from answering a question directly?" asked Ronald Levine, lawyer for Bonnie Bowser, Fattah's former campaign treasurer, also charged in the case.

Asked later whether he had misled the FBI in the past, Lindenfeld offered an equivocating answer: "I have lied to avoid telling the truth."

Lindenfeld, 61, pleaded guilty in 2014 to playing a role in securing an illegal $1 million campaign loan to save Fattah's foundering mayoral campaign.

His testimony Thursday came as part of a plea agreement with prosecutors who now seek to link Fattah to the same crime.

They allege that after securing the loan from former Sallie Mae CEO Al Lord, Fattah later paid off the debt using stolen charitable donations and federal grant funds.

In a separate scheme, prosecutors say, Fattah sought to pay Lindenfeld for work he did on the mayoral campaign by steering congressional earmarks to a sham nonprofit he encouraged the consultant to create.

Lindenfeld - a thick-shouldered Princeton University graduate with a list of past clients that includes John F. Street, Michael Nutter, Ed Rendell, Bill Clinton, and Barack Obama - testified Wednesday that he staked his consulting firm, LSG Strategies, as collateral for the loan Lord made to Fattah in 2007.

The check was issued to Lindenfeld's company instead of the campaign because it violated the city's limits on political contributions. But Lindenfeld told jurors the understanding from the start was that Fattah would be responsible for paying the debt.

Keeping a distance

In questioning Thursday, Fattah lawyer Samuel Silver balked at that story, stressing that prosecutors had produced no documentary evidence that the congressman knew anything about the loan. What's more, Lindenfeld previously had expressed concerns over Fattah's poor record as a fund-raiser.

"You were already worried about the campaign's ability to raise money," Silver said. "You didn't bother to get anything in writing from the congressman even though you were putting your name and company on the line?"

That was the point, Lindenfeld responded: to keep Fattah's name as far from the transaction as possible.

"I had multiple conversations with him," he said. "He didn't write documents."

Fattah was equally eager to keep his fingerprints off the scheme devised a year later to pay $95,000 he owed LSG Strategies after the 2007 campaign, Lindenfeld testified.

Prosecutors have alleged that with no money to pay the debt, Fattah encouraged Lindenfeld to set up a nonprofit, and promised to steer millions in taxpayer dollars to it through his seat on the House Appropriations Committee.

Blue Guardians

As Lindenfeld described it to jurors, it was Fattah who came up with the organization's name, Blue Guardians, and who helped craft the wording on its grant applications.

The congressman, he said, also devised the organization's stated mission - raising awareness about the pollution caused by cruise ships and water skis along the Atlantic Coast and in the Caribbean.

Although Blue Guardians twice sought to land funding from the National Oceanic and Atmospheric Administration, an attempted $500,000 appropriation was scuttled in 2010 after an Inquirer reporter called Lindenfeld asking questions about the organization.

"That was the straw that broke the camel's back," he said. "I didn't think we wanted any more inquiry into the relationship we had with Congressman Fattah."

Silver, Fattah's lawyer, offered another explanation for why Lindenfeld was so quick to turn on the congressman when federal authorities first approached him in 2014: After the Blue Guardians plan fell apart, the operative was still angry that Fattah had never paid him for his work.

"Would you say winning is pretty important in your business?" the defense lawyer asked.

Lindenfeld shrugged and responded, "I could say the same about yours."

Testimony in the case is expected to resume Friday.