DES MOINES, Iowa — Democrat Theresa Greenfield narrowly leads Republican Sen. Joni Ernst by three percentage points in one of the most competitive races in the country, according to the latest Des Moines Register/Mediacom Iowa Poll.
The poll, released Saturday evening, shows Greenfield leading 45% to 42% among likely voters. Another 3% say the would vote for someone else, 2% say they wouldn't vote in the race and 7% are unsure.
The Register reports that these results are "largely unchanged" since June, when Greenfield led Ernst by 46% to 43%.
The poll collected a total of 803 responses from Iowa adults from Sept. 14 through 17. Of those responses, 658 say they are likely voters. The margin of error lies plus or minus 3.5 percentage points for Iowa adults questioned.
Those asked of likely voters have a margin of error plus or minus 3.8 percentage points, the Register reports.
The Register reports among likely voters, 75% say they know who they're voting for this November. Another 14% say they could still change their minds before then, however.
Ernst supporters are "firm" in their choices, 87% say their minds are made up and 13% say they could be persuaded. Meanwhile, 83% of Greenfield supporters say their minds are made up and 16% say they could be persuaded.
Take a look at the Des Moines Register/Mediacom Iowa Poll methodology
What else did the poll find?
Majority of likely voters want more from Sen. Ernst
The poll says 56% of likely voters say Ernst hasn't done enough for Iowans while in Congress. That includes 19% of voters that say they plan to vote for her in November.
It also includes 25% of people who say they support President Donald Trump for re-election this November. A total of 33% of likely voters say the senator has done enough to help Iowans and 11% are unsure.
Ernst's favorability among all Iowans hovers around 44%, according to the Register. In June it was at 45%.
However, some of those who viewed her unfavorably in June had a change of heart. The percentage ticked up from 40% in June to 44% in September.
Ernst's coronavirus response approval rating dipped from 42% in June to 38% in the latest poll. Her disapproval rating on her response has risen from 34% to 41%.
How voters feel about Ernst's relationship with President Trump
Respondents also answered questions on Ernst's relationship with the president; 43% say the relationship between the two is "about right." However, 37% say she is "too close" to Trump. The poll found 4% say she's not close enough and 17% aren't sure.
The poll also found that 71% of Democratic likely voters say Ernst is too close to Trump, while three-fourths of Republican voters say she gets it about right.
As for independent voters, 43% say the senator is too close to Trump and 37% say she has the right relationship. Only 3% say Ernst isn't close enough to him.
How Iowans view candidates for the U.S. Senate
The Register found that Ernst performs best with evangelicals, whom of which prefer her by 58% to 28% over Greenfield. Rural voters also approve of Ernst more, winning them 54% to 36%.
Voters ages 35 to 54 also favor Ernst 52% to 35%.
However, Greenfield takes the cake among independent and women voters. Those that describe themselves as independent are more likely to support the first-time candidate and businesswoman.
The poll found 44% of independent voters say Greenfield is "about right" and 25% say she's too liberal. Greenfield leads with independent voters 47% to 32% over Ernst.
Greenfield leads 53% to 33% among all women; 49% to 35% among mothers of kids under 18 years old; 44% to 27% among independent women; 47% to 42% among married women; 64% to 20% among unmarried women; 53% to 33% among white women without a college degree and 51% to 39% of white women with a college degree.
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