The death of liberal Supreme Court Justice Ruth Bader Ginsburg on Friday evening at age 87— and the political fight over her seat to follow — promises to further upend the battle for Senate control just six weeks before Election Day.

President Trump and Senate Republicans are pledging to move ahead with a nominee and hold a confirmation vote despite their insistence not to do so when Justice Antonin Scalia died some nine months before Election Day 2016. As of Monday evening, it certainly looks like they have the votes to do so. And as my colleague Amy Walter has written, that controversial decision ultimately may not move the president’s sagging re-election numbers, making him still the decided and steady underdog against former Vice President Joe Biden.

But in a Senate map where Republicans are almost entirely on defense, and the closest races that will determine the majority could be decided by a few thousand of votes, Ginsburg’s passing and subsequent high court vacancy could have an impact, even if it only moves numbers marginally. Because over a

More from the Cook Political Report