Recently , it 's been candidates who have been in vote - getting , bruising primaries . A platoon of Democrats are mulling primary elections in Ohio , Florida , Maryland , Texas , Pennsylvania and Illinois . Of the nine Senate seats contested as toss - up or competitive in 2016 , none are held by 2020 .
Recently , it 's been Republicans who have been in attention-getting , bruising primaries . A platoon of Democrats are mulling Senate bids in Ohio , Florida , Maryland , California , Pennsylvania and Illinois . Of the nine Senate seats rated as toss-up or competitive in 2016 , seven are held by Republicans .