Campaigning is done right happens between elections. In most countries you only have 4/6 weeks. As Kim Campbell of Canada famously said an election is not the time to debate issues. Now the US has a much longer campaign period.. and elections every 2 years. They are always campaigning.
Every US President is constantly campaigning. Not necessarily for his own re-election but to create public pressure on Congress to support his agenda, and then to get votes for his endorsed successor.
