The reason sanctuary cities exist is because law enforcement in those cities needs community buy-in to help solve other more important crimes. A witness to a murder or a victim of domestic violence might not come forward if they are undocumented and might get deported for talking to the police.
No way to really track it because by definition they're going unreported but I can only imagine what kind of horror show is going unreported due to these raids.
He didn't "handily win" he won by 1-2 points in the swing states.
It tracks with an anti-incumbent sentiment, people are not happy with inflation so they voted against the incumbent, they're still not happy and still voting against the incumbent.