New York (CNN) Donald Trump sought to regain control of his campaign Wednesday, turning attention away from the turmoil roiling his operation with a blistering denunciation of the character, career and qualifications of Hillary Clinton.

After enduring weeks of self-inflicted wounds, the speech was Trump's most professional political address since he became the presumptive nominee in early May. It seemed to fuse his volatile, off-the-cuff political style with a more traditional brand of political discourse that puts reasoned arguments before voters as they make their choice for President.

Speaking from a teleprompter, with occasional asides, Trump appeared to be road testing a more scripted, subdued style ahead of next month's Republican National Convention -- even as he was unsparing in his rebuke of Clinton.

The presumptive Democratic nominee is "a world-class liar," Trump said during a 40 minute speech in New York in which he slammed Clinton for everything from using a private email server to backing free trade.

"Just look at her pathetic email and server statements ... or her phony landing in Bosnia, where she said she was under attack but the attack turned out to be young girls handing her flowers."

Painting Clinton as the candidate of inertia and the unsatisfactory status quo, he called her message "old and tired."

"Her message is that things can't change," Trump said. "My message is that things have to change -- and this is our one chance to do it and may be our only chance to do that change."

In delivering the fiery speech against Clinton, firing campaign manager Corey Lewandowski and actively working to rebut Clinton's remarks Tuesday in real time, Trump's campaign is working to reassure Republicans the billionaire is up to the job. Republicans have expressed concern about and distanced themselves from his controversial comments of late and some GOP delegates are actively exploring ways to block Trump at the convention in Cleveland next month.

Clinton, who spent Tuesday firing off her own assault on Trump, hit back at his counter-attack during a visit to North Carolina, interrupting a speech on her economic policy to accuse the presumptive Republican nominee of attacking her because he lacks substance.

"I guess my speech yesterday must have gotten under his skin because right away he lashed out on Twitter with outlandish lies and conspiracy theories and he did the same in his speech today," Clinton said.

Photos: Donald Trump's rise Photos: Donald Trump's rise President-elect Donald Trump has been in the spotlight for years. From developing real estate and producing and starring in TV shows, he became a celebrity long before winning the White House. Hide Caption 1 of 37 Photos: Donald Trump's rise Trump at age 4. He was born in 1946 to Fred and Mary Trump in New York City. His father was a real estate developer. Hide Caption 2 of 37 Photos: Donald Trump's rise Trump, left, in a family photo. He was the second-youngest of five children. Hide Caption 3 of 37 Photos: Donald Trump's rise Trump, center, stands at attention during his senior year at the New York Military Academy in 1964. Hide Caption 4 of 37 Photos: Donald Trump's rise Trump, center, wears a baseball uniform at the New York Military Academy in 1964. After he graduated from the boarding school, he went to college. He started at Fordham University before transferring and later graduating from the Wharton School, the University of Pennsylvania's business school. Hide Caption 5 of 37 Photos: Donald Trump's rise Trump stands with Alfred Eisenpreis, New York's economic development administrator, in 1976 while they look at a sketch of a new 1,400-room renovation project of the Commodore Hotel. After graduating college in 1968, Trump worked with his father on developments in Queens and Brooklyn before purchasing or building multiple properties in New York and Atlantic City, New Jersey. Those properties included Trump Tower in New York and Trump Plaza and multiple casinos in Atlantic City. Hide Caption 6 of 37 Photos: Donald Trump's rise Trump attends an event to mark the start of construction of the New York Convention Center in 1979. Hide Caption 7 of 37 Photos: Donald Trump's rise Trump wears a hard hat at the Trump Tower construction site in New York in 1980. Hide Caption 8 of 37 Photos: Donald Trump's rise Trump was married to Ivana Zelnicek Trump from 1977 to 1990, when they divorced. They had three children together: Donald Jr., Ivanka and Eric. Hide Caption 9 of 37 Photos: Donald Trump's rise The Trump family, circa 1986. Hide Caption 10 of 37 Photos: Donald Trump's rise Trump uses his personal helicopter to get around New York in 1987. Hide Caption 11 of 37 Photos: Donald Trump's rise Trump stands in the atrium of the Trump Tower. Hide Caption 12 of 37 Photos: Donald Trump's rise Trump attends the opening of his new Atlantic City casino, the Taj Mahal, in 1989. Hide Caption 13 of 37 Photos: Donald Trump's rise Trump signs his second book, "Trump: Surviving at the Top," in 1990. Trump has published at least 16 other books, including "The Art of the Deal" and "The America We Deserve." Hide Caption 14 of 37 Photos: Donald Trump's rise Trump and singer Michael Jackson pose for a photo before traveling to visit Ryan White, a young child with AIDS, in 1990. Hide Caption 15 of 37 Photos: Donald Trump's rise Trump dips his second wife, Marla Maples, after the couple married in a private ceremony in New York in December 1993. The couple divorced in 1999 and had one daughter together, Tiffany. Hide Caption 16 of 37 Photos: Donald Trump's rise Trump putts a golf ball in his New York office in 1998. Hide Caption 17 of 37 Photos: Donald Trump's rise An advertisement for the television show "The Apprentice" hangs at Trump Tower in 2004. The show launched in January of that year. In January 2008, the show returned as "Celebrity Apprentice." Hide Caption 18 of 37 Photos: Donald Trump's rise A 12-inch talking Trump doll is on display at a toy store in New York in September 2004. Hide Caption 19 of 37 Photos: Donald Trump's rise Trump attends a news conference in 2005 that announced the establishment of Trump University. From 2005 until it closed in 2010, Trump University had about 10,000 people sign up for a program that promised success in real estate. Three separate lawsuits -- two class-action suits filed in California and one filed by New York's attorney general -- argued that the program was mired in fraud and deception. Trump's camp rejected the suits' claims as "baseless." And Trump has charged that the New York case against him is politically motivated. Hide Caption 20 of 37 Photos: Donald Trump's rise Trump attends the U.S. Open tennis tournament with his third wife, Melania Knauss-Trump, and their son, Barron, in 2006. Trump and Knauss married in 2005. Hide Caption 21 of 37 Photos: Donald Trump's rise Trump wrestles with "Stone Cold" Steve Austin at WrestleMania in 2007. Trump has close ties with the WWE and its CEO, Vince McMahon. Hide Caption 22 of 37 Photos: Donald Trump's rise For "The Apprentice," Trump was honored with a star on the Hollywood Walk of Fame in January 2007. Hide Caption 23 of 37 Photos: Donald Trump's rise Trump appears on the set of "The Celebrity Apprentice" with two of his children -- Donald Jr. and Ivanka -- in 2009. Hide Caption 24 of 37 Photos: Donald Trump's rise Trump poses with Miss Universe contestants in 2011. Trump had been executive producer of the Miss Universe, Miss USA and Miss Teen USA pageants since 1996. Hide Caption 25 of 37 Photos: Donald Trump's rise In 2012, Trump announces his endorsement of Republican presidential candidate Mitt Romney. Hide Caption 26 of 37 Photos: Donald Trump's rise Trump speaks in Sarasota, Florida, after accepting the Statesman of the Year Award at the Sarasota GOP dinner in August 2012. It was shortly before the Republican National Convention in nearby Tampa. Hide Caption 27 of 37 Photos: Donald Trump's rise Trump appears on stage with singer Nick Jonas and television personality Giuliana Rancic during the 2013 Miss USA pageant. Hide Caption 28 of 37 Photos: Donald Trump's rise In June 2015, during a speech from Trump Tower, Trump announced that he was running for President. He said he would give up "The Apprentice" to run. Hide Caption 29 of 37 Photos: Donald Trump's rise Trump -- flanked by U.S. Sens. Marco Rubio, left, and Ted Cruz -- speaks during a CNN debate in Miami on March 10. Trump dominated the GOP primaries and emerged as the presumptive nominee in May. Hide Caption 30 of 37 Photos: Donald Trump's rise The Trump family poses for a photo in New York in April. Hide Caption 31 of 37 Photos: Donald Trump's rise Trump speaks during a campaign event in Evansville, Indiana, on April 28. After Trump won the Indiana primary, his last two competitors dropped out of the GOP race. Hide Caption 32 of 37 Photos: Donald Trump's rise Trump delivers a speech at the Republican National Convention in July, accepting the party's nomination for President. "I have had a truly great life in business," he said. "But now, my sole and exclusive mission is to go to work for our country -- to go to work for you. It's time to deliver a victory for the American people." Hide Caption 33 of 37 Photos: Donald Trump's rise Trump faces Democratic nominee Hillary Clinton in the first presidential debate, which took place in Hempstead, New York, in September. Hide Caption 34 of 37 Photos: Donald Trump's rise Trump apologizes in a video, posted to his Twitter account in October, for vulgar and sexually aggressive remarks he made a decade ago regarding women. "I said it, I was wrong and I apologize," Trump said, referring to lewd comments he made during a previously unaired taping of "Access Hollywood." Multiple Republican leaders rescinded their endorsements of Trump after the footage was released. Hide Caption 35 of 37 Photos: Donald Trump's rise Trump walks on stage with his family after he was declared the election winner on November 9. "Ours was not a campaign, but rather, an incredible and great movement," he told his supporters in New York. Hide Caption 36 of 37 Photos: Donald Trump's rise Trump is joined by his family as he is sworn in as President on January 20. Hide Caption 37 of 37

Trump went further than he has before in laying the foundations of a governing agenda, promising in his first 100 days in office to appoint judges to uphold the Constitution, to change immigration rules to give good paying jobs to Americans and to stand up to countries that cheat on trade.

He said he would cancel regulations that send jobs overseas, lift restrictions on energy production and pass a "massive tax reform" to create millions of jobs.

"There is one common theme in all of these reforms," he said. "It's going to be America first."

Trump also attempted to frame the kind of wider vision of national purpose that presidential candidates often attempt to give a more lofty thematic foundation to their campaigns.

He said he would get America working again and parents dreaming big for their children again and to help people believe in their country once more.

"We are going to make America rich again. We are going to make America safe again. We are going to make America Great Again," he said.

Lambasting a "rigged" political system dominated by special interests, Trump also stressed his outsider credentials and urged Americans to approach the general election as jurors.

"Come November, the American people will have a chance to issue a verdict on the politicians that have sacrificed their security, betrayed their prosperity and sold out their country -- and I mean totally sold out their country," Trump said.

Trump's speech aimed to dissect Clinton's personality and positions on issues ranging from trade and foreign policy to paint the former secretary of state as someone who is out of touch with workers and has enriched herself "at America's expense."

Clinton, he said, "may be the most corrupt person ever to seek the presidency of the United States."

Trump accused Clinton of using the State Department as a "personal hedge fund" while she enriched herself and her husband former President Bill Clinton by in effect peddling influence for cash.

Without citing evidence, Trump accused Clinton for instance of giving "China millions of our best jobs and effectively let China completely rebuild itself. In return, Hillary Clinton got rich!"

He tied what he said was Clinton's malfeasance while in office to an argument over trade deals such as the North American Free Trade Agreement that were ratified during Bill Clinton's administration.

He lambasted Clinton for her previous support of the Trans-Pacific Partnership trade deal, a position she has since reversed, and and argued she would enact free trade policies as president that would upend the U.S. economy.

"We will lose jobs, we will lose employment, we will lose taxes," Trump said. "We will lose everything. We will lose our country."

"She has betrayed the American worker on trade at every single stage of her career," he said.

Trump's jeremiads over free trade deals were one of the most effective strategies that he adopted in his primary campaign and helped attract blue collar voters especially in rust belt states. Some Democrats are deeply concerned that he could damage the former secretary of state in Midwestern swing states if he is able to make equally successful use of the strategy in the general election.

Trump also lambasted Clinton on foreign policy, accusing her of "almost single-handedly destabilizing the entire Middle East" during her time as secretary of state. Clinton's campaign sees her record as the top U.S. diplomat as an asset, but Republicans are convinced they can undermine her case to be commander-in-chief by pointing to failures on her watch, including the deaths of four Americans in Benghazi and the ill-fated "reset" of relations with Russia.

"The Hillary Clinton foreign policy has cost America thousands of lives and trillions of dollars -- and unleashed ISIS across the world. No secretary of state has been more wrong, more often and in more places than Hillary Clinton," Trump said.

"Her decisions spread death, destruction, and terrorism everywhere she touched," Trump said, accusing Clinton of handing Libya to "ISIS barbarians" after a US-backed intervention and of helping Iran become the dominant power in the Middle East.

Once again, Trump falsely claimed to have argued against the war in Iraq before the U.S. invaded the country. Trump was publicly supportive of the war a month before Congress voted to authorize the use of military force and praised the war's direction in the early months of the campaign.

And he said Clinton may be disqualified from the presidency on the basis that the emails on her private email server may have been hacked by foreign enemies -- though there's no evidence of such a breach.

"While we may not know what is in those deleted emails, our enemies probably know every single one of them," Trump said of the emails Clinton deleted and did not hand over to the State Department.

After weeks of being on the receiving end of Clinton's rhetoric, Trump sought to turn her words against her. Clinton frequently tells audiences Trump lacks the "temperament" for the presidency -- a criticism Trump threw back at her.

"Hillary Clinton wants to be President," he said. "But she doesn't have the temperament, or, as Bernie Sanders' said, the judgment, to be president. She believes she is entitled to the office."