To avoid removal, Trump needs senators representing only 7 percent of the country to support him
If we assume a party-line vote (which is essentially what happened in the House), 53 percent of senators would oppose impeachment but more than half the country would live in states whose senators favored impeachment. (For these calculations, we assigned half of the states population to each senator to account for states with split-party senators. Independents were presumed to support removal.)
That opposition to impeachment also means that a party-line Senate vote would even less accurately reflect public polling. The difference between our theoretical Senate vote margin and the Post poll is nine points; for the House it was a bit under five points.
Isnt this just a way to say that the Senate isnt representative of the population? Sure. But that manifests in interesting ways on this particular issue.
Consider, for example, that it requires 67 votes in the Senate to oust Trump from office. That means that 34 votes are needed to preserve his position. Even if he were deeply unpopular, if Trump maintained support from senators in 17 states, he could keep his job. Meaning, in the most extreme scenario, that he could be impeached but not removed from office if senators from the 17 least-populous states representing about 7 percent of the population decided to stand by him.
https://www.washingtonpost.com/politics/2019/12/19/avoid-removal-trump-only-needs-senators-representing-percent-country-support-him/