Original sentence: Andrew Marr says that neither he nor leading Conservatives believe that a Corbyn-led Labour Party is unelectable under any circumstances, but either another financial crisis or an "improbable" leftward shift in the views of "swing voters" in marginal constituencies would need to happen first.Some senior Labour figures such as Peter Mandelson have argued that Labour is unelectable with Corbyn as leader, though Mandelson also advises party members unhappy with Corbyn to wait for polls to show he is unelectable before working to replace him