As pointed out down-thread, there's a lot more to this than a simple website (voter analytics/GOTV stuff just for starters), and the potential user base/traffic load is enormous (ramping up particularly as you near election day).
Just as a data point in support of the kind of traffic that US presidential elections can drive for election-related things, I happened to be working on the web team for a major American newspaper circa the '08 election and we saw something like 1.2Bn page views the month leading up the election. (Traffic analytics wasn't my team, so that's a vague memory of being told that from five years ago. Grain of salt, etc.) This is for simple news/op-ed, mind you, and only one source of many for that information. I have no problems believing that the main web presences of the two candidates would see even more traffic, and they'd likely be more complicated under the hood than "hit homepage, follow article link, read article."
Just as a data point in support of the kind of traffic that US presidential elections can drive for election-related things, I happened to be working on the web team for a major American newspaper circa the '08 election and we saw something like 1.2Bn page views the month leading up the election. (Traffic analytics wasn't my team, so that's a vague memory of being told that from five years ago. Grain of salt, etc.) This is for simple news/op-ed, mind you, and only one source of many for that information. I have no problems believing that the main web presences of the two candidates would see even more traffic, and they'd likely be more complicated under the hood than "hit homepage, follow article link, read article."