Coffin ran for the NL NDP in the
2015 provincial election in
Waterford Valley. She ran for the provincial party leadership election in April 2018, losing to MHA
Gerry Rogers. After Rogers resigned, Coffin was
elected leader unopposed in March 2019. She was confirmed as the party's new leader at a news conference on March 5, 2019. Coffin is a former associate president of the provincial party. Coffin led the party into the
2019 provincial election; despite only nominating 14 candidates (out of a possible 40) the party won 3 seats. Coffin won
St. John's East-Quidi Vidi holding it for the NDP, while the party led
St. John's Centre, and won an upset in
Labrador West. Coffin led the party into the
2021 provincial election. She was personally defeated in her district of
St. John's East-Quidi Vidi; while the party held St. John's Centre and Labrador West. Coffin filed for a recount. On May 12, 2021, Supreme Court Justice Donald Burrage rejected Coffin's bid for a recount, arguing that there was not sufficient evidence. On October 16, 2021, Coffin lost a
leadership review by party members. She resigned on October 19 and was replaced by MHA
Jim Dinn as interim leader. On August 15, 2025,
John Abbott resigned his seat in the
House of Assembly. He did this to avoid a legal battle stemming from the disputed results in the
St. John's East-Quidi Vidi riding. In the
2025 provincial election, Coffin ran as an independent candidate in both
Carbonear-Trinity-Bay de Verde and
Harbour Grace-Port de Grave on a platform of election reform, losing in both. She is the first person since
Henry Renouf in the
1869 Newfoundland general election to run in more than one riding. == Electoral history ==