AUGUSTA, Maine (AP) — Former U.S. Sen. Olympia Snowe is joining a national organization that highlights the adverse effects of America's partisan political divide and suggests ways to promote unity, the organization announced Wednesday.

Snowe, a Republican, is joining the Bipartisan Policy Center as a senior fellow. She will co-chair its newly formed Commission on Political Reform, the center said.

The commission's diverse group of 30 leaders will conduct a series of "National Conversations on American Unity" to discuss the effects of political polarization and to develop recommendations to help Americans achieve shared national goals.

The Bipartisan Policy Center was founded in 2007 by former Senate majority leaders Howard Baker, Tom Daschle, Bob Dole and George Mitchell. It is the only Washington, D.C.-based think tank that actively promotes bipartisanship.

Snowe, long known as a moderate who bucked the Republican line on some issues, surprised Maine's political establishment in February 2012 when she announced she would not seek a fourth Senate term. She has been critical of polarization and partisanship that she feels have made it harder for Congress to make decisions on important issues.

Her departure led to crowded primaries and finally the election of her independent successor, Angus King, whose campaign theme was restoring a cooperative spirit in Washington.

Bipartisan Policy Commission President Jason Grumet said the organization welcomes Snowe's "independent voice, passionate ideals, collaborative instinct and wise counsel."

Snowe said she "couldn't be more pleased and excited to join this dynamic and growing organization, whose mission is absolutely essential at this moment of unparalleled polarization in our nation, and certainly in our government."