Appel worked for 12 years as a financial consultant with Merrill Lynch and UBS Paine Webber. Appel served on several committees in the Iowa Senate – the Agriculture committee; the State Government committee; the Ways and Means committee; and the Education committee, where she was vice chair. She also served as vice chair of the Administration and Regulation Appropriations Subcommittee. Appel was elected in 2006 with 12,827 votes, defeating Republican opponent Julian B. Garrett by 772 votes. Appel's first bill in the Senate was a proposal to raise the minimum wage in Iowa to $7.25. During her time in the State Senate Appel favored the Equal Pay For Equal Work Act As a member of the Iowa Senate, Appel was appointed to be the Assistant Majority Leader. Appel lost her bid for re-election to state Representative Kent Sorenson in 2010, who won the election by a 58% to 40% margin.
Political positions
Appel is pro-choice and supports same-sex marriage. She has stated her support for the Affordable Care Act and would not repeal it. Appel endorses Senator Tom Harkin's proposal to raise the minimum wage to $10.10 per hour. On immigration, she has stated her support for increased border security and a pathway for citizenship for the estimated 11 million undocumented immigrants currently in the United States. On gun rights, Appel has stated that the gun-show loophole should be closed and that background checks should be required wherever a gun is purchased. On foreign policy, she has stated her opposition to Russia's incursions into Ukraine, though noted that "she said she doesn't hear Iowans talking much about foreign policy."
2014 congressional election
Appel ran for an open congressional seat in Iowa's 3rd congressional district. Incumbent congressman Tom Latham retired. She initially stated she would run for the seat, before announcing that she would not run, citing family obligations, before reversing her decision once again to commit to the race. She faced Republican nominee David Young in the general election. David Young won the election with 52.8% of the vote to Appel's 42.2%. Appel was endorsed by EMILY's List, a political action committee that supports pro-choice female Democrats, and the American Federation of State, County and Municipal Employees. The Democratic Congressional Campaign Committee added her to their jumpstart program, which provides financial support. Stuart Rothenberg of Roll Call rated the race as "Pure Toss Up". In May 2014, a Republican spokesperson accused Appel of plagiarizing text from another candidate's website, something her campaign manager said he takes responsibility for.