The article content could not be retrieved. The text supplied in place of the article is only a browser challenge page ("Just a moment… Enable JavaScript and cookies to continue"), which is an anti-bot verification screen rather than the news story itself. As a result, no information about the Sheffield election, the Southey by-election or the shifting national political landscape referenced in the headline is available to summarise.

Based on the title alone, the piece appears to be an opinion article in The Star discussing how the electoral outlook in Sheffield — particularly around a Southey by-election — has become more uncertain against a changing national political backdrop. However, the substantive claims, figures and context cannot be confirmed, because the actual body text was not accessible. To provide an accurate summary, the full article would need to be supplied or fetched successfully.