Two of my grown-up children pointed me to Electoral-vote.com for the last presidential campaign in 2004, and I notice it’s up again for this campaign.
The site follows the polls, all the polls, and uses them to create a composite of where the different polls stand. The chart here is one of several available, this one charting the polls over time, since earlier this year.
I’ve always liked the line charts for business charts, because they show change over time. In this one, following polls, you can see how the indications of electoral vote for each of the two candidates have risen and fallen. The text annotations link events to the progress of the charts.