DFL State Sen. Terri Bonoff leads GOP U.S. Rep. Erik Paulsen by two points in a poll released Thursday by a national Democratic group that also showed two in 10 voters were still undecided in the race.

The Minnetonka Democrat leads Paulsen 40 to 38 in the poll conducted by the Democratic Congressional Campaign Committee. Twenty-two percent of voters are still undecided, according to the survey of 353 likely general election voters in Minnesota's Third Congressional District.

Respondents were selected from a voter file. The poll, conducted Sep. 12, has a margin of error of 5.2 points.

A spokesman for Paulsen immediately dismissed the poll. 

"The DCCC's 'poll' is a desperate ploy that no reputable pollster would even put their name on," said John-Paul Yates, a spokesman for Paulsen's campaign, calling into question the credibility of a poll he called a "stunt."

Sean Oyaas, a spokesman for Bonoff's campaign, said in a statement that the poll "is a testament to the hard work and positive message of Terri’s campaign."

Bonoff has attacked Paulsen for not yet saying whether he will vote for GOP presidential nominee Donald Trump in November. Paulsen has previously said that he would support the nominee, but in recent months backtracked saying Trump has not earned his vote. Paulsen has declined to elaborate on what it would take for Trump to earn his vote.

A previous poll by a Republican-affiliated group conducted Aug. 9-12 found Paulsen ahead of his Democratic challenger.