Sen. Joni Ernst (R-IA) leads Democrat Senate candidate Theresa Greenfield in one of the pivotal races for control of the U.S. Senate, according to a poll released Thursday.

An AARP poll found that Ernst leads Greenfield 50 to 45 percent among Iowa likely voters. The incumbent Iowa conservative also leads Greenfield 50 to 46 percent among voters ages 50 and older.

Ernst’s lead goes beyond the poll’s 3.5 percent margin of error against Greenfield.

The survey’s five-point lead for Ernst shows an upsurge in polling for the incumbent Iowa conservative.

One August Public Policy Polling survey found that Greenfield led Ernst by three points, a Data for Progress poll in August had Greenfield leading by two points, and an RMG Research poll in August had Greenfield leading Ernst by four points.

A Monmouth University poll in August had Ernst leading Greenfield by three points.

The AARP poll also found that President Donald Trump has a two-point advantage over former Vice President Joe Biden among likely Iowa voters and voters older than 50. The 45th president leads Biden 47 to 45 percent among likely voters and 48 to 46 percent among elderly voters.

The poll also found that elderly voters plan to vote at a polling place rather than by mail. Among voters above 50 years old, 44 percent will use mail-in ballots, 13 percent will vote during the early voting period, and 39 percent plan to vote on Election Day.

Nancy LeaMond, the AARP executive vice president, said in a statement on Thursday that elderly voters will play an influential role in the November elections.

“We believe 50-plus voters are going to play a critical role in this year’s election,” LeaMond said. The AARP executive noted that, while voters above age 50 comprise 45 percent of the voting population, they account for 56 percent of the ballots cast in 2016.

“They punch above their weight,” LeaMond added.

Although Greenfield has attempted to paint herself as a moderate Democrat, she enflamed controversy last week when she claimed that there is “systemic racism” in America’s law enforcement.

Melissa Deatsch, a spokesperson for the Ernst campaign, said in a statement on Wednesday:

As radical liberals and the cancel culture movement sweeps through our communities, Theresa Greenfield put her liberal extremist views on full display calling all Iowa police departments racist. It’s clear that Greenfield is the candidate of the far left, not an independent leader who will stand up for all Iowans, like Joni Ernst.

AARP commissioned Fabrizio Ward and Hart Research to conduct the poll in Iowa. The polling firm interviewed 800 likely Iowa voters between August 30 and September 5, a sample of 800 voters and an “oversample” of 800 voters who are 50 and older.

The firm conducted the interviews via landline and cell phone, and the survey has a margin of error of 3.5 percent.

Sean Moran is a congressional reporter for Breitbart News. Follow him on Twitter @SeanMoran3.