This story is published in a content partnership with POLITICO. It was originally reported by Burgess Everett and John Bresnahan on politico.com on October 12, 2020.Just about the only thing holding the Republican Party together right now is Amy Coney Barrett.President Donald Trump’s sinking poll numbers are putting once-safe Senate seats in play and threatening deeper losses in the House. Republicans are unenthusiastic about defending Trump’s handling of the coronavirus pandemic or commenting…