After Boris Johnson and David Davis make their cabinet exit, how could Theresa May be replaced?

SPECULATION about Theresa May's tenancy at No 10 Downing Street has dominated the week, but how could she actually be replaced?

As two of Theresa May's top government team seemed to desert her, with the resignations of Brexit boss David Davis and foreign secretary Boris Johnson, political pundits began to wonder how long the beleaguered prime minister could hold.