Since graduating from College of the Atlantic, she has resided on North Haven, a small island community off the coast of Rockland.

[1] As the leader of Common Cause, Pingree was active in the organization's programs in media reform, elections, ethics, and money in politics.

She supported net neutrality, mandatory voter-verified paper ballots, public financing of congressional elections, national popular vote (a workaround for the Electoral College), and an independent ethics commission for Congress.

During her tenure as a state legislator, Pingree made nationwide headlines when she authored the nation's first bill regulating prescription drug prices, Maine Rx.

[13] She was endorsed by a number of labor organizations and many individuals and state officials, including Congressman Rush D. Holt Jr.; Congresswoman Jan Schakowsky; Maine Senate Majority Leader Libby Mitchell; former Maine Senate Assistant Majority Leader Anne Rand; State Representative Paulette Beaudoin; progressive writer and activist Jim Hightower; the United Auto Workers; Planned Parenthood, and the League of Conservation Voters.

She overcame strong anti-Democrat and anti-incumbent political sentiment to become just one of eight House Democrats to receive a higher percentage of the vote than in 2008.

[1] On February 29, 2012, an Associated Press story mentioned that Pingree was starting to circulate petitions to run for the U.S. Senate seat vacated by the retirement of Olympia Snowe, which she confirmed on The Rachel Maddow Show later that night.

[18] In late 2017, Pingree's name was mentioned as a potential Democratic candidate for governor of Maine, to succeed term-limited incumbent Paul LePage.

In September 2010, a video surfaced on the internet showing Pingree at Portland International Jetport disembarking from a private jet owned by her then-fiancé, hedge fund manager S. Donald Sussman.

[28] Pingree opposes granting the president fast track authority in negotiating trade agreements, having voted against doing so on June 12, 2015.

[38] She has spoken out against the 2011 Supreme Court ruling McComish v. Bennett, which limits public financing systems for congressional campaigns.

In June 2011, she voted for House Resolution 292, preventing President Barack Obama from deploying ground forces in Libya.

[39] In 2017, Pingree did not attend the inauguration of Donald Trump, instead visiting a Planned Parenthood center and a business owned by immigrants.

[44] Alongside her House colleagues, Pingree has urged President Joe Biden to declare a national climate emergency.

On June 18, 2011, Pingree married S. Donald Sussman, a hedge fund manager,[58] in a private ceremony at the couple's home in North Haven, Maine.

[59] Until June 1, 2015, Sussman owned a 75%[60] stake in MaineToday Media, the owners of the Portland Press Herald, Kennebec Journal, and Morning Sentinel, in addition to sitting on the board of directors.

[64] Pingree and her daughter Hannah co-own the Nebo Lodge Inn & Restaurant on Maine's North Haven Island.