WASHINGTON (CBSNewYork/AP) — Newly released documents about a now-defunct business owned by Donald Trump reveal strategies for enticing people to enroll in real estate seminars even if they couldn’t afford it. That has opened the presumptive Republican nominee up to fresh criticism from Hillary Clinton that he took advantage of vulnerable Americans.

Clinton took to Twitter Wednesday to call Trump University “a fraudulent scheme used to prey upon those who could least afford it.”

Trump University was a fraudulent scheme used to prey upon those who could least afford it. https://t.co/oz5ycvA2J1 pic.twitter.com/9ue4nVEdwt — Hillary Clinton (@HillaryClinton) June 1, 2016

Trump University's own employees described it as a "scam.” https://t.co/xDeDI1sPpR pic.twitter.com/qA2MtslUVs — Hillary Clinton (@HillaryClinton) June 1, 2016

Clinton campaign aides suggested the likely Democratic nominee would use Trump University as part of a broader effort to cast Trump as a callous businessman who promises Americans ways to get ahead, but is only concerned with enriching himself. As part of that effort, Clinton has previously hammered Trump for appearing to cheer for the collapse of the U.S. housing market and for failing to make good on pledges to donate to veterans until he was pressured to follow through by the media.

According to a new Quinnipiac poll, Clinton has a slim 45 percent to 41 percent lead over Trump nationally.

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Trump University is the target of two lawsuits in San Diego and one in New York that accuse the business of fleecing students with unfulfilled promises to teach secrets of success in real estate. Plaintiffs contend that Trump University gave seminars and classes across the country that were like infomercials, constantly pressuring customers to buy more and, in the end, failing to deliver.

Trump has maintained that customers were overwhelmingly satisfied with the offerings — a point that his attorneys repeated after the new documents were unsealed Tuesday. Last Friday, a judge who has earned Trump’s scorn sided with attorneys for The Washington Post who argued that the public had a right to know what was previously confidential.

As Trump steamrolled through the GOP primary, some of his rivals raised Trump University as a liability for the businessman and at least five different outside groups mentioned the business in attack ads. Florida Sen. Marco Rubio also used Trump University in his campaign speeches as part of his failed attempt to blunt the real estate mogul’s political rise.

“It was targeted at people that were struggling,” Rubio said during a March 1 campaign appearance. He said they were retirees, single mothers and young people trying to start a business. “They were people that were hurting, and they specifically targeted them.”

Rubio said last week that he’s eager to help the party defeat Clinton.

While details about the business did little to stop Trump in the primary, Clinton allies say GOP candidates were too slow in raising concerns and inconsistent in their attacks. Democrats have vowed to avoid repeating those same mistakes in the fall campaign.

The documents released Tuesday give Clinton some fresh ammunition for raising concerns about Trump’s business dealings. The “playbooks” for Trump University outline how employees should guide customers through “the roller coaster of emotions” once they have expressed interest in the courses.

“The motivation that they experienced can die quickly as the realities of their daily lives take over. It is our job to rekindle that motivation — to make them once again see the potential of achieving their dream,” according to a “sales playbook.”

Trump University offered a three-day seminar for $1,495, using it as a springboard to sell more expensive “Trump Elite” packages for up to $34,995 a year.

“You don’t sell products, benefits or solutions — you sell feelings,” according to the sales playbook.

Trump University’s core customers are identified in the documents as male heads of households between 40 and 54 years old with annual household incomes of at least $90,000, a college education and a net worth of more than $200,000.

During one-on-one conversations, “you may begin with some small-talk to establish rapport but do not let them take control of the conversation,” a playbook reads. “You must be very aggressive during these conversations to in order to push them out of their comfort zones.”

“If they complain about the price, remind them that Trump is the BEST!! This is the last real estate investment they will ever need to make.”

For those who have hit credit limits, employees are told to suggest they dip into savings or identify other “seed capital.”

“Money is never a reason for not enrolling in Trump University; if they really believe in you and your product, they will find the money,” a playbook reads.

The documents unsealed Tuesday do include testimony from several satisfied customers.

“Much of the unsealed evidence, including declarations and surveys from former Trump University students, demonstrates the high level of satisfaction from students and that Trump University taught valuable real estate information,” said Jill Martin, vice president and assistant general counsel for The Trump Organization. “Trump University looks forward to using this evidence, along with much more, to win when the case is brought before a jury.”

The 6-year-old case in San Diego is scheduled to go to trial shortly after the November presidential election.

Trump has railed against U.S. District Judge Gonzalo Curiel, who ordered the documents unsealed. At a rally in San Diego on Friday, he accused the judge of being “hostile” and a “hater of Donald Trump,” and raised questions about his ethnicity.

“The judge, who happens to be, we believe, Mexican, which is great, I think that’s fine,” Trump said of Curiel, who was born in the U.S.

It was the second time Trump has brought up the judge’s ethnicity as he complained about his treatment.

Curiel late Tuesday ordered some released documents to be resealed and resubmitted with sections blacked-out. He said some records had “mistakenly” been released Friday, when he ordered some documents made public.

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