The debate on Tuesday between Senator Tim Kaine of Virginia and Gov. Mike Pence of Indiana was sloppy, contentious and unlikely to reshape the course of presidential history. What was supposed to be the nice-guy tête-à-tête was instead a snippy, tit-for-tat exchange in the key of conventional politics. Here are some of our top takeaways from the evening:

A Republican Split Over Putin

Under sustained pressure from Mr. Kaine, Mr. Pence declined for almost the entire evening to break from Donald J. Trump on any questions of judgment and policy. He calmly sidestepped a flurry of attacks over Mr. Trump’s offensive remarks, opting to ignore them rather than defend his running mate, and delivered his own, sanitized version of the Trump-Pence message. In a tone of reassurance, Mr. Pence insisted there was nothing improper about Mr. Trump’s refusal to release his tax returns.

A stark exception came on the subject of Russia: Without criticizing Mr. Trump, Mr. Pence offered an assessment of the Russian president, Vladimir V. Putin, that was at diametric odds with his running mate’s views. While Mr. Trump has praised Mr. Putin’s strength and control over Russia, Mr. Pence repeatedly called him a “small and bullying leader.” And Mr. Pence denied having called Mr. Putin a stronger leader than President Obama, though he did precisely that last month.

This rare point of fracture may set up an uncomfortable moment for Mr. Trump the next time he is pressed for his views on Mr. Putin.

Kaine’s Biden Impression

With his badgering approach to Mr. Pence, Mr. Kaine seemed to be channeling Vice President Joseph R. Biden Jr., who interrupted, laughed and mocked his way through his 2012 debate with Representative Paul D. Ryan. That method worked for Mr. Biden, undermining his opponent’s ability to deliver a coherent message and essentially turning the debate into a wasted moment for Republicans, who had needed to make it count.