McCabe's case is a little more complex. Trump grilled him when he became acting FBI director last year (after Comey's dismissal) about whom he voted for in the 2016 presidential election and about his wife's Democratic campaign for Virginia state legislature. But while McCabe voted in the 2016 GOP primary, Virginia doesn't have party registration, and he doesn't appear to have voted in other primaries in recent years. So it's theoretically possible he chose the GOP primary because he wanted to vote against Trump. Still, if he were a Democratic-leaning voter, he'd have been missing out on that party's competitive primary.
But basically none of that is accurate. Rosenstein is originally from Pennsylvania. He did serve as an assistant U.S. attorney in Maryland, where he was selected by Bush for a U.S. Court of Appeals judgeship in 2007. But that nomination was actually blocked by Maryland's Democratic senators because they felt Rosenstein didn't have enough Maryland “roots.” And Maryland records show he's been registered as a Republican in Montgomery County since 1998.
This is also somewhat the case with Peter Strzok, the FBI agent who was demoted for writing Trump-bashing text messages. While Strzok's comments in those texts were clearly and frequently anti-Trump, he also derided Democratic politicians like Hillary Clinton, Bernie Sanders, former attorney general Eric Holder and former Maryland governor Martin O'Malley and even criticized Chelsea Clinton as “self-entitled.” He at one point mused that someone had guessed that he voted for Republican Ohio Gov. John Kasich in the 2016 presidential race. (He did not confirm whether he had, though, and the last Virginia primary in which he voted was the 2008 Democratic primary.)
None of this is to suggest that any of these men are incapable of anti-Trump bias simply because they may more closely align with the Republican Party; there are certainly plenty of Never Trump Republicans in the political establishment, and it's possible that's also the case in the law enforcement establishment.
But it is notable that the men behind this supposed deep-state conspiracy aren't obvious political foils for Trump and don't neatly fit into Trump's overly simplistic me-vs.-the Democrats dichotomy.
Alice Crites contributed to this report.