Here's a look at where Kaine stands on three of those questions.
Kaine supports President Obama's international trade deal, known as the Trans-Pacific Partnership, and voted to give the president special authority to negotiate the agreement.
"I see much in it to like. I think it’s an upgrade of labor standards. I think it’s an upgrade of environmental standards. I think it’s an upgrade in intellectual property protections," the former governor of Virginia told The Intercept this week, adding that he has concerns about other aspects of the accord, specifically regarding how disputes between companies and foreign governments would be resolved.
Clinton supervised the negotiations of the Trans-Pacific Partnership as Obama's secretary of state and supported the deal at the time. Recently, though, she has said she opposes the final version of the agreement.
"I did say, when I was secretary of state three years ago, that I hoped it would be the gold standard," Clinton said last year. "In looking at it, it didn't meet my standards, my standards for more new, good jobs for Americans, for raising wages for Americans."
Bernie Sanders, Clinton's unsuccessful rival in the Democratic primary, also opposes the deal, as does Donald Trump, her GOP opponent.
Kaine says he supports the Dodd-Frank Act, the comprehensive and complex financial reform that Congress passed in 2010. At the same time, Kaine has argued for less stringent regulations on some aspects of banks' operations, and he subscribes to one of the chief conservative critiques of the reform.
Specifically, Kaine agrees with many opponents of the Dodd-Frank Act that the rules are placing undue burdens on local and regional banks. "It’s important you don’t treat every financial institution the same," Kaine told The Washington Post. “It wasn’t credit unions that tanked the economy. It wasn’t local community banks that tanked the economy."
On Monday, Kaine signed a letter to the Consumer Financial Protection Bureau, calling on the agency to "tailor" regulations to focus on larger institutions. The senator also signed a second letter to Janet Yellen, the head of the Federal Reserve, and other officials asking them to allow banks to report their liquidity once a month instead of every day.
Liquidity is a measure of a financial institution's ability to pay its debts in the short term. When investors and depositors lose confidence in a bank's ability to make good on its obligations, the result can be a run on the bank. From the perspective of liberal reformers, regular reporting is crucial to ensuring the stability of the financial system, since a run can develop in just a few days.
Kaine's position on abortion is complicated.
Like Vice President Biden, Kaine describes himself as a Catholic who opposes abortion on account of his faith. He has supported the Hyde Amendment, which generally bars Medicaid patients from using federal funds to pay for abortions. He has also supported requiring parental consent for mothers seeking abortions, and as governor of Virginia, he allowed drivers to put license plates with the words "Choose Life" on their cars.
At the same time, Kaine has voted against bills to defund Planned Parenthood, and he supports the Supreme Court's 1973 ruling in Roe v. Wade.
"I have a traditional Catholic personal position, but I am very strongly supportive that women should make these decisions and government shouldn't intrude," Kaine told CNN last week.
Correction: This post has been revised to reflect the fact that the Hyde Amendment includes exceptions for cases of rape and incest or when the life of the mother is in danger, and that some states provide funding for other abortions as well.
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