Lincoln was the first woman and the first Arkansan to serve as chair of the U.S. Senate Committee on Agriculture, Nutrition and Forestry.

[9] After graduating from college, Lincoln served as a staff assistant for U.S. Representative Bill Alexander, a Democrat from Arkansas's 1st congressional district.

[19][20] While in the House, she was one of only 17 Democrats to vote for the Teamwork for Employees and Managers Act of 1995 which sought to change federal employment laws.

She voted in favor restricting class action lawsuits and tightening rules on personal bankruptcy.

In 2007, Lincoln played a key role in brokering the compromise that led to passage of the Food, Conservation, and Energy Act of 2008.

Also known as the “farm bill,” this legislation provides resources for nutrition, conservation, rural development, and renewable energy.

In 2009 she spoke out in opposition to the pro-labor union bill known as the Employee Free Choice Act; this garnering her the praise of conservative interest groups like Americans for Tax Reform, but also bitter criticisms from labor unions, who publicly threatened to discourage Arkansas' remaining Democratic-leaning voters from voting for her.

[29] In November 2009, Lincoln voted against bringing Guantanamo Bay prisoners to the United States for trial.

[32] With the Obama administration having become hugely unpopular in her home state, Lincoln's re-election strategy in 2010 was to depict herself to Arkansas voters as independent of the Democrats.

After first narrowly surviving a primary challenge by the state's then-Lieutenant Governor Bill Halter with an early endorsement from former President and Governor of Arkansas Bill Clinton, Lincoln lost in November 2010 to Republican congressman John Boozman by a landslide, 58% to 37%.

[34] Lincoln also helped form the Moderate Dems Working Group, a coalition of moderate Senate Democrats whose stated goal is to work with Senate leadership and the administration toward finding bipartisan solutions to controversial political issues.

In addition, she co-founded and currently co-chairs Third Way, a moderate think-tank whose self-described goals are "an economic agenda that is focused on growth and middle class success; a culture of shared values; a national security approach that is both tough and smart; and a clean energy revolution.

Lincoln remained in Washington after her re-election loss in November 2010, working as Special Policy Advisor at the firm of Alston & Bird.