Donald Trump's unorthodox candidacy blossomed into an unorthodox presidency. In the White House, Trump carries with him all of the complex, tricky and fraught behaviors and tendencies that powered him through the 2016 campaign. He also carries with him the decisions and interactions that led him to victory - including a staff that may have some nebulous ties to a Russian government that wanted to see him victorious.
Trump's sudden firing of FBI Director James Comey was an accelerant to the smoldering question of Russia's role in the election. After various people emerged from the White House to insist that the termination had nothing to do with the investigation being conducted by the FBI, Trump on Thursday announced to all of America that, no, that was a big part of it.
When the interview in which he said that became public, it took only minutes for observers to wonder how this didn't constitute obstruction of justice, given that Trump was essentially firing someone looking into what his campaign had done. And once you start wandering into the territory of crimes or misdemeanors, others will rapidly venture one step further and start speculating about impeachment.
Those engaging in such speculation, though, are warned: There's one little number that makes such a move unlikely. That number is 84 percent, Trump's job approval rating among Republicans in the most recent weekly average from Gallup.
Why's that one number so important? Allow me to explain.
On Thursday, shortly before the interview with Trump aired, NBC's political team released numbers from a poll conducted with the firm SurveyMonkey. A majority of Americans disagreed with Trump's decision on Comey, it turns out, with 54 percent saying that Comey's termination was inappropriate. A majority also said that allegations that the campaign was in contact with Russian actors was a serious issue, and not a distraction.
On the Comey question, majorities of Democrats and independents think that the move was inappropriate - but three-quarters of Republicans are fine with it.
On the question of whether the allegations are serious, there's a similar split. Republicans think it's a distraction. Everyone else disagrees.
The initial excuse for the firing offered by the White House was that it was rooted in criticism from a deputy attorney general of Comey's handling of the investigation into Hillary Clinton's use of a private email server. While a plurality of Americans believed that the firing was a function of Trump's concern about the Russia investigation, Republicans largely accepted the White House's original argument.
That pattern - Republicans being enthusiastic, while independents are skeptical and Democrats furious - is consistent across views of Trump. No president has been more polarizing in Gallup's history of approval polling, and no president has been viewed less positively at this point in his first term. That pattern is the reason why. Democrats loathe him and independents are something shy of lukewarm, which strong Republican support can't outweigh enough to keep him from record lows.
What's more, this pattern holds on nearly every issue. On Thursday, Quinnipiac University unveiled new polling looking at signature policy issues of the Trump administration. The health-care bill that passed the House this month continues to be broadly unpopular, but almost half of Republicans view it approvingly.
Trump's nebulous tax plan is also broadly disliked - again, except among Trump's own party.
Those issues, of course, overlap with the concerns of Trump's allies on Capitol Hill. Having Republican voters broadly approving of Trump's initiatives is important to Hill Republicans for a variety of reasons, including that they want those policy measures to pass, too. (The American Health Care Act, for example, was a bill developed by congressional Republicans that Trump championed with relative indifference.)
Keeping Hill Republicans happy is important for Trump, too, because they control the relative few points of leverage over his presidency.
If there is to be an independent investigation of the possible links between Trump's campaign and Russia, either Trump needs to appoint someone - unlikely - or Hill Republicans have to leverage their control of Congress to create a robust independent body, to change the law or to bring pressure against Trump. Those are the only options, and all come down to the will of Trump or members of his party. If things were to progress to the point of impeachment, same deal: A Republican Congress would need to move the process forward.
At this point, it's not simply a coincidence that Republicans approve of what Trump is doing and of what is happening in Congress. Trump's popularity with Republicans is driving popularity of Congress. Since his election, views of Republican leaders in Congress have spiked among members of their party.
Quinnipiac asked how a House candidate's demonstration of support for Trump might affect a voter's support. Overall, it was a liability - but among Republicans, support for Trump was seen as either unimportant or as a boon.
If Republican members of Congress are confident that their party's voters will support them if they ally with Trump, that's all that many will need to hear. The electoral fights in the GOP over the past eight years have been largely primary fights: Republicans battling each other for the right to dispatch a Democrat in November. The average general-election margin of victory for Republicans in 2016 was 33.2 percentage points, according to Ballotopedia. Last November, 216 Republicans won by 10 points or more, a function of the power of incumbency, of the informal movement of voters into politically similar regions and of gerrymandering.
But why are Republicans so much more favorable to Trump and his actions? Part of it is the increase in partisanship over recent years. Part of it, too, is that Trump is bolstered by positive coverage in outlets that more Republicans watch.
Last October, Suffolk University polled on the presidential race, including a question about the respondents' most-trusted news or commentary outlet. Fox News was the most popular outlet overall - thanks to the fact that more than half of Republicans and Trump voters said it was what they trusted most.
How did Fox cover the Comey firing? Slate said the network was covering it from "an alternate reality." The Times wrote that the attitude on Fox toward Comey's firing was almost "celebratory." The Post noted that Fox and other conservative outlets were "closing ranks" behind Trump on the subject.
This couples with new research published this week by Pew Research showing that Republicans are suddenly much less likely to say that the media's criticism of politicians helps keep those politicians in line.
The partisan numbers on that question always align with the party in the White House, but the gap between the parties has never been bigger.
Trump's current favorable numbers actually aren't very good for Trump. In the 2016 election, nearly a third of the votes he got were from independents - enough to give him the slight edge he needed to win the Electoral College.
If his support from independents stays as soft as it is now, it's hard to see how he wins a second term.
But that's not the Hill Republicans' problem. If Trump stays popular with Republicans, if that popularity continues to rub off and if conservative news outlets continue to help keep all of that in place, there's little political incentive for Republicans in safe (or safe-ish) seats to call for an independent investigation, much less an impeachment.
If that 84 percent approval starts to sag significantly? Trump moves from political asset to political liability. And nothing in this world moves as quickly as a politician looking for distance from something unpopular.