- Voters draw their economic verdict on the incumbent by June.
- Late summer polls, after the primary bump and before the convention bumps, show the underlying state of the race.
- National polls become volatile and misleading through the convention and debate season.
- The results of a campaign's actions take a few weeks to show up in polls, immediate poll reactions are often misleading.
- The candidate making 'bold' or 'dramatic' moves late in the campaign is losing.
Presidential campaigns are large, slow moving things. It takes a lot of thought and effort to shape the opinions of a couple hundred million people. There is little room to change things in the last quarter of a campaign, if your strategy is not working and the underlying trend is against you, then you are probably out of time to change strategies.
