Local races often have limited publicly available polling. A useful race page can still identify the jurisdiction, link to primary sources, and state clearly that no qualifying survey is available.
Keep different evidence separate
Election results describe votes cast in a past election. Fundraising measures money raised. Endorsements show organizational or individual support. None of these is interchangeable with a survey of the current electorate.
Check the geography
District boundaries and electorates can change between cycles. A historical comparison should identify the jurisdiction and population it actually describes.