If Sen. Elizabeth Warren (D-Mass.) had a plan for pulling ahead in Iowa, it may be working.

A poll released on Wednesday by the nonprofit organization Focus on Rural America has Warren leading the field among Iowa Democrats likely to participate in next year's caucuses with 20 percent of the vote. She comes in ahead of Sen. Kamala Harris (D-Calif.) at 18 percent, former Vice President Joe Biden at 17 percent, Sen. Bernie Sanders (I-Vt) at 12 percent, and South Bend Mayor Pete Buttigieg at 10 percent. Warren, Harris, and Biden are all within the margin of error.

This comes in the days following the first round of presidential debates, during which Warren was widely seen as the winner of the first night and Harris of the second night. In this poll, Warren jumped up 12 percentage points compared to a previous poll conducted in March, while Harris rose nine points. In the opposite direction, Biden and Sanders both slipped compared to four months ago. A total of 88 percent of those surveyed said they have a positive opinion of Warren, with this giving her the highest favorable rating of any candidate. Biden, for comparison, is viewed favorably by 74 percent of those surveyed.

Twenty-six percent of respondents said the debates had "quite a bit" of an influence on their opinion, while 37 percent said it had "some" impact. Still, Harris seems to have benefited the most, as when respondents were asked to name candidates they're now actively considering due to their debate performance, 34 percent said Harris, while 16 percent said Warren.

A previous Suffolk University/USA TODAY Poll had shown Warren in third place in Iowa, coming in behind Biden and Harris.

Focus on Rural America's poll was conducted from June 29-July 1 by David Binder Research by speaking to 600 registered voters over the phone who said they would likely participate in the Iowa caucuses. The margin of error is four percentage points. Read more at Focus on Rural America. Brendan Morrow