Both of those numbers are down slightly but within the margin of error and well within the normal range for each question. Overall belief in Mueller's fairness has been between 56 and 60 percent for the past four months. And GOP confidence in Mueller has dropped from a high of 54 percent to 35 percent today, but that drop came in the latter half of 2017, with 34 percent calling Mueller “fair” in December.
Polling has long shown growing GOP skepticism of law enforcement, and this poll is no exception. Twenty-eight percent of Republicans approve of how the FBI is handling its job — down from 40 percent in January 2017 — but given the dearth of polling in the intervening year, it's not clear whether the Nunes memo had any impact. It would seem just as likely, given the long-term trend on Mueller's investigation, that it's more a symptom of that steady erosion.
(While Republicans' views of the FBI have dimmed, Democrats' approval of it increased from 57 percent in January 2017 to 67 percent today. That has kept overall approval of the bureau steady.)
At the same time, there is a credible case to be made that the GOP base is already primed and ready to side with Trump no matter what Mueller finds. Last month's Quinnipiac poll showed 83 percent of Republicans regarded the investigation as a “witch hunt,” while 12 percent said it was legitimate. The new poll shows Republicans say 58 percent to 28 percent that the FBI is biased against Trump.
And remarkably, the new poll also shows Republicans are about evenly split about whether it is appropriate for Trump to ask Justice Department employees for loyalty — something he has reportedly alluded to on numerous occasions. Forty-six percent of Republicans say that's okay with them, while 44 percent disagree.
Whether the memo has bearing on the Russia investigation is very much in dispute, with Trump claiming it vindicates him but other Republicans saying it is only about alleged abuses by law enforcement that have no bearing on the Russia probe.
But Trump's comments have hinted at a broader hope that it would call the Russia investigation into question. And so far, the Nunes memo doesn't seem to have moved the needle.