This outlook seems bleak for the Democrats, but it’s possible that Mueller’s testimony could work in their favor, even if it doesn’t do much to shift views of Trump overall. They’ve faced across-the-board stonewalling from the Trump administration in response to requests for testimony and documents, so getting Mueller to testify at all was a rare bit of success because they’ve had very few splashy public hearings so far. If Mueller’s testimony does, in fact, turn out to be a “public spectacle” — as Attorney General Bill Barr has predicted — that could help refocus Democratic voters and the 2020 candidates on the report’s findings and potential misconduct by the president. After all, Mueller’s news conference in May, at which he spoke for less than 10 minutes and restated the report’s primary conclusions without taking questions, was enough to spark a new wave of calls for impeachment. Transforming the report into a true priority for voters could be harder, though — when a CNN poll in March asked respondents to name their top issue for 2020, none mentioned the Russia investigation.

There is another possible upside to Mueller’s testimony for Democrats, though — hearing from Muller could stop people from developing a more positive opinion about Trump. After all, his approval ratings remain low despite a strong economy, and they haven’t improved substantially since Mueller’s investigation ended. “We shouldn’t conclude that the Democrats are failing because they’re not having an impact on Trump’s approval rating,” Schickler said. “If their steady drumbeat of investigations and hearings can prevent Trump’s approval rating from increasing, that’s another kind of success.”