Tim Kaine and Mike Pence clash during VP debate

Tim Kaine, left, and Mike Pence shake hands before their vice-presidential debate at Longwood University in Farmville, Va., Oct. 4, 2016. At left is the moderator, CBS's Elaine Quijano.

Sen. Tim Kaine of Virginia and Gov. Mike Pence of Indiana on Tuesday night reached for the kind of sober, policy-laden discussion that has eluded their high-profile running mates, but soon descended into a gloves-off clash over the economy, Donald Trump’s taxes, Hillary Clinton’s emails and the need for change in Washington.

Known as mild-mannered politicians, both men used the opening minutes of their only debate to make an affirmative case for their tickets. Pence argued that Trump’s business talent and brash style make him the only one able to shake up Washington. Kaine bragged about Clinton’s government experience and insisted that America needs someone with her maturity and judgment.

But it did not take long before Pence, the Republican vice-presidential nominee, and Kaine, the Democratic nominee, shifted to attack mode, with each of them interrupting the other and assailing the opposing running mates as professionally and morally unfit to occupy the Oval Office.

Kaine quickly mentioned the report by The New York Times over the weekend that Trump had amassed a nearly $1 billion business loss that might have allowed him to avoid paying taxes for almost two decades. Kaine said that Trump’s business career and the way he has conducted his campaign should disqualify him in the eyes of voters.

“Donald Trump always puts himself first,” Kaine said, saying he built businesses on the “backs of the little guy.” Kaine said, “I can’t imagine how Gov. Pence can defend the insult-driven, me-first” campaign that Trump leads.

Pence did defend his running mate, insisting that Trump had “built a business, through hard times and good times.” He said the tax returns proved that Trump faced “some pretty hard times” decades ago but “used the tax code just the way it was supposed to be used.” He said that Trump’s businesses created thousands of jobs.

Pence tried to shift the debate to Clinton’s actions, saying that she had put the nation at risk by using a private email server, and he accused her being the “architect” of a weak foreign policy that had caused problems around the world.

“We’ve weakened America’s place in the world,” Pence said, accusing Clinton of leading a foreign policy that has left large portions of the world “literally spinning out of control.”

While vice-presidential candidates always use their debates to promote and defend their running mates, Pence had the heavier political burden on Tuesday after a weeklong barrage of outbursts from Trump that renewed questions about his temperament and his ability to win in November.

Trump did Pence no favors by delivering a widely panned debate performance against Clinton last week in which he skimmed over some policy specifics and misstated others. He also struggled to explain his early support for the Iraq War and his lead role in pushing the myth that President Barack Obama was not born in the United States.

Clinton was particularly effective in baiting Trump over his past insults of women, which led him to try to justify once calling the comedian Rosie O’Donnell a “pig” and a “slob” and describing a past Miss Universe as “Miss Piggy.”

For several days Trump could not let go of the fight over the beauty pageant winner, Alicia Machado; on Friday he was still posting on Twitter–in the predawn hours–about how Machado was “disgusting” and claiming without evidence that she once participated in a sex tape.

Trump, in an interview, shrugged off the possibility that these attacks might hurt him with undecided female voters, saying they “need to know that this girl is not a girl scout,” and then going on to unleash one on Clinton over her husband’s past marital infidelities.

Trump’s finances also came under scrutiny over the weekend after The New York Times obtained three pages of his previously unreleased tax records showing a $916 million loss on his 1995 returns that may have allowed him to avoid paying federal income taxes for nearly two decades. The Trump campaign alternately threatened to sue over the revelations and portrayed Trump as a “genius” for his use of the tax code.

The stormy week lifted Clinton’s standing in several new national and swing-state polls. As a result, Pence was under pressure to make a case for Trump’s ideas while trying to explain or minimize some of his recent remarks.

But Pence’s advisers also said they would use the forum to frame the Republican ticket as agents of change at a time when voters are deeply contemptuous of Washington. Republicans hoped Pence could use the debate to raise questions about Clinton’s use of a private email server and her record while secretary of state and her links to Wall Street, issues that have been obscured by Trump’s erratic behavior over the past week.

The debate expectations for Pence did not mean Kaine would get off easy, however. Clinton is nearly as unpopular as Trump, with both candidates still viewed unfavorably by majorities of likely voters, according to recent polls.

Clinton has been battling questions about her honesty and trustworthiness since she started running for president in April 2015, amid revelations about her private email server and the disclosure that she had deleted more than 30,000 messages from her tenure as secretary of state because she deemed them personal.

Kaine and Pence prepared for the debate with the goal of being character witnesses for their running mates, a traditional role for vice-presidential candidates. Yet, according to their advisers, neither Kaine nor Pence was under any illusion that they were likely to erase many bad impressions of Clinton and Trump that voters already held.

Instead, Kaine aimed to keep the onus on Trump while outlining Clinton’s plans to try to create jobs, increase wages and improve the Affordable Care Act and other government programs that help families, young people, veterans and others.

Kaine was also expected to try to force his counterpart to choose between defending his running mate’s inflammatory statements and retaining his own viability as a potential future candidate. One issue Kaine was likely to raise: tax returns. While Trump has refused to make his public, Pence quietly released his own last month.

The faceoff between Kaine and Pence also offered a glimpse of a more conventional political campaign between two buttoned-up and graying white men.

Both are longtime officeholders and disciplined public speakers. Neither projects much charisma, but they are experienced debaters who know how to redirect questions for their own advantage. Both arrived at the debate site in Farmville, Virginia, aiming to do exactly that, determined to use their own brief moment in the political spotlight to raise questions less about each other than about Trump and Clinton.

Kaine, a onetime litigator who became Richmond’s mayor before becoming governor and senator, enjoys a genial reputation and can come across as friendly if slightly awkward fatherly type. But he has spent much of his time in the campaign seeking to prosecute the case that Trump is unfit for the presidency. Occasionally offering a middling impression of Trump’s Queens accent, he has targeted the Republican over comments on race and gender as well as his business practices.

Pence is a former radio talk show host who was a member of the House before becoming governor. He is an earnest conservative and just about the antithesis of his flamboyant running mate. He was expected to use the matchup to continue what he has done on the campaign trail, assail Clinton in harsh terms as emblematic of a corrupt status quo.

Third-party candidates such as the Libertarian Party’s vice-presidential nominee, former Gov. William F. Weld of Massachusetts, did not participate in the debate because their running mates did not meet the threshold of support in recent national polls to qualify under the rules of the bipartisan Commission on Presidential Debates.