While the Red Green Alliance had a pretty mediocre election given that SPP nearly collapsed and even lost support in their Copenagen strongholds they gained a lot in the province - especially Jutland, and became more of a national party. Building on their good municipal election in 2013.
Found this list over 40%+ gains:
Randers Nord 59%
Esbjerg City 55%
Tønder 53%
Frederikshavn 50%
Odense Øst 48%
Mariager Fjord 46%
Randers Syd 42%
Vejen 42%
Aabenraa 41%
Odense Syd 40%
Just to be clear, are those in percentage points or percent increases?