Updated at 2:02 p.m. ET
For supporters of President Trump's impeachment, Robert Mueller's testimony will be a critical juncture.
The former special counsel's appearances before the House judiciary and intelligence committees on Wednesday will be perhaps the last chance to make this case while the whole nation is watching.
There's evidence that Mueller's words matter. Mueller's single, brief statement about the report was shown to be persuasive to lawmakers on the fence.
When he last spoke publicly, at the end of May, his remarks were followed by a series of Democrats announcing that they would support opening an impeachment inquiry into the president.
On the day of Mueller's statement, eight House Democrats openly declared their support for impeachment. By the end of the week, another half dozen lawmakers had come to that conclusion.
In fact, 49 Democrats have announced their support for impeachment since Mueller's public remarks on May 29. That's more than half of the 93 lawmakers NPR has recorded as publicly backing an impeachment inquiry into the president.
These 93 lawmakers represent roughly 40% of the House Democratic caucus. There are currently 235 Democrats in the House of Representatives.
For the most part, leadership and moderates are on one side of the divide, progressives on the other. This was succinctly illustrated at the NAACP convention on Monday.
House Speaker Nancy Pelosi, D-Calif., made no mention of impeachment during her remarks.
In contrast, pro-impeachment lawmaker Rep. Rashida Tlaib, D-Mich., had preceded her onstage. To a raucous crowd, Tlaib kicked off her comments by saying, "I'm not going nowhere! Not until I impeach this president!"
Follow NPR's tracker to see if the testimony causes a spike in calls for an impeachment inquiry. Below, find out where each member of the House stands ahead of the hearings.