Stylistically, Mike Pence did an excellent job at the vice presidential debate. When he had points he wanted to make, he made them in a clear and straightforward manner. When his opponent repeatedly tried to interrupt him, he remained utterly unruffled. He’s clearly a very skilled salesman.

But the substantive problem is that the product Pence really has to sell is a Donald Trump presidency. And that’s a very tough sell indeed.

When things turned back to Trump personally, Pence had a variety of tricks that he fell back on. Sometimes, he repeated the same positive points about Trump (he’s a good businessman!). Sometimes, he tried to turn Tim Kaine’s accusations back on him. Sometimes he simply ignored Kaine’s points entirely. And sometimes he just denied reality.

Take this riff from Kaine, in which he rattled off a non-exhaustive list of Trump’s top insults during the campaign.

KAINE: Donald Trump has called Mexicans rapists and criminals. He has called women dogs, pigs, disgusting. He said a judge was unqualified for a Federal lawsuit because his parents were Mexican. He went after John McCain, a POW, and said he was not a hero because he had been captured. If you want to have a society where people are respected and respect laws, you cannot have someone at the top who demeans every group he talks about. I cannot believe that Gov. Pence would defend the insult-driven campaign that Donald Trump has run.

There’s not really a good way for Pence to respond to all these true statements, so he feigned disbelief. “Did you all just hear that ours is an insult-driven campaign?” he asked, before trying to change the subject to Hillary Clinton’s “basket of deplorables” comment to make the case that she is the real insult champion. This, of course, is patently absurd.

Later, when Kaine brought up Trump’s frequent praise of Russian leader Vladimir Putin, saying they were just “facts” about Trump, Pence simply tried to pretend it wasn’t so, claiming, “Most of what you said is completely false, and the American people know that.” Yet Trump has praised Putin again and again.

When Kaine pushed on why Trump has refused to disclose his tax returns despite decades of precedent and Trump’s previous promises that he would, the best Pence could come up with was that, well, he doesn’t legally have to. “Donald Trump has filed over 100 pages of financial disclosure, which is what the law requires,” Pence said. He also reiterated that Trump “said he will” release his returns eventually, though apparently he’s in no rush to do so before the election.

At various other points, Pence signaled with his body language (head shakes) or brief interruptions like the simple word “no” that viewers shouldn’t believe the nasty-sounding comments Kaine was attributing to Trump.

And when both moderator Elaine Quijano and Kaine quizzed Pence on Trump’s stated desire to get all unauthorized immigrants out of the country, Pence bobbed and weaved, stressing how Trump wanted to deport “criminals,” saying that a “deportation force” already exists, and not really mentioning what would happen to unauthorized immigrants who hadn’t committed crimes.

We won’t know for a while whether Pence’s performance was something that swing voters will find to be convincing or effective. (Historically, vice presidential debates have tended not to affect polls.)

But substantively, it’s important to remember that that’s what it was — a performance. He was making his best effort to sell the very badly flawed product of Donald Trump.