Iowa Poll: Democrat Leads Joni Ernst

Republican Senator Joni Ernst, up for re-election in Iowa, narrowly trails Democratic challenger Theresa Greenfield, according to a Des Moines Register/Mediacom Iowa poll released on Saturday.

Greenfield, a Des Moines real estate developer, had the support of 46% of likely voters against 43% who said they would back Ernst if the election were held today.

Veteran pollster J. Ann Selzer, president of Selzer and Co., which conducted the survey, said Ernst was trailing a general-election challenger, either actual or theoretical, for the first time since 2014.

The poll was conducted June 7-10 and had a margin of error of plus or minus 3.8 percentage points among 674 likely voters, making it a statistical tie.

President Donald Trump has already started to promote Ernst’s re-election as Republicans defend a number of Senate seats that will determine control of the chamber in November. Republicans have a 53-47 seat majority at the moment.

Ernst hasn’t so far been seen as the most endangered GOP incumbent; the Cook Political Report recently rated the race as “leans Republican.”

Ernst’s job approval rating began to slip this year, to 47% in March from 57% a year earlier. It was 49% in the latest survey against 39% who disapprove.

Greenfield, who is less well known, was viewed favorably by 41% and unfavorably by 20%. Many Iowans -- 39% -- said they don’t know enough about her to offer an opinion.

That makes the next few months key, as Ernst and Greenfield attempt to define the challenger to voters. Ad spending in the state is already heavy.