Cindy Trigg of Douglas County has decided to pull out of the race against Dean Heller.
Trigg, a Democrat, announced her candidacy for the Congressional District 2 earlier this year, saying the Republican incumbent was out of step with his constituency.
She said she made the decision to end the campaign after a sudden series of professional obligations arose.
"While I believe that Dean Heller can be defeated next year, I cannot dedicate the time required to mount a winning campaign."
She said she will assist the Democratic nominee for the seat "in pushing a message that Democrats are the party of job creation, economic recovery, healthcare reform, energy independence and, most importantly to me, education reform."
Heller is serving his second two-year term. He has not yet said what his plans are, although some Republicans are urging him to run against U.S. Sen. Harry Reid, D-Nev.