Collins was the Deputy State Treasurer of Massachusetts prior to being elected to the Senate as a representative of Maine in January of 1997. She has served in the senate since then, with her current term ending in 2021. Collins has been re-elected to the Senate three times already. She is a republican, but stands for more moderately-right values than fellow republican senators.
Angus King is the former governor of Maine, and was elected to the US Senate in 2013. King is an independent, and was re-elected to the Senate in November of 2018. He stands for moderately liberal values.