Basically it's a key to candidates because it is considered to influence the overall result of the president election. Democratic and Republicans both have a good chance to gain a win.
It was primarily tied up in the slave economy.
Before the Roman Republic was transformed into an empire, the nation had a Senate and an executive branch with Consul's acting as leaders of the nation. Rome had an representation in place that was very advanced for an ancient civilization.
Hope my answer helped you :)
