When the vice-presidential nominees debate Tuesday, they'll be asked to explain their stances on issues where they disagree with each other — and with running mates Donald Trump and Hillary Clinton. A look at where Democratic Sen. Tim Kaine and Indiana Gov. Mike Pence, a Republican, stand on the key policy disputes:
On abortion
Kaine: A Catholic who personally opposes abortion, as governor he backed some limits on abortion. In 2005, he said he had a "faith-based" opposition to abortion. He has voted in favor of policies supporting a woman's right to choose since coming to the Senate in 2012.
Pence: In 2011, he said that he longed "for the day that Roe vs. Wade is sent to the ash heap of history, when we move past the broken hearts and broken minds of the past 38 years." He voted for the criminalization of abortion services during his tenure in Congress.
On the environment
Kaine: He voted to curb carbon pollution and against the Keystone XL pipeline. He opposed an amendment that would have closed a loophole exempting fracking water from being regulated under the Safe Drinking Water Act. He backs offshore drilling in the Atlantic.
Pence: He has denied the existence of climate change and voted to eliminate funding for climate-change education programs and to bar the Environmental Protection Agency from regulating greenhouse gas emissions. He supports fossil fuel development and offshore drilling.
On foreign policy