An extensive literature demonstrates that local campaign efforts in the UK generally pay electoral dividends for parties. As a result, rational parties focus campaign efforts most in seats where the electoral outcome is not pre-determined and where a few more votes either way could change the result. An important indicator of where such constituencies can be found is provided by prior election results, and research has shown that rational parties tend to focus their campaigns most heavily on those seats where the previous election was close and less in seats where in the past they either lost badly or won comfortably. However, much less attention has been given to how local parties react to new information showing how the competitive situation in their area is changing as a general election approaches. We use data from a rare set of local opinion polls conducted by Lord Ashcroft in British constituencies in the run-up to the 2015 UK General Election. Although hampered by their generally small size, limited fund-raising capacity, and reliance on volunteers, local parties do appear to respond to new information. Our results indicate that parties tend to put more effort into local campaigns in seats where an opinion poll had been carried out than in otherwise similar seats where one had not. And, the more competitive the poll suggested their race was, the more resources they devoted to it.