Sen. Chuck Grassley, 88, is running for an eighth term in the U.S. Senate.

Grassley, a Republican, made his announcement Friday in a Tweet posted at 4 a.m., which is when he wakes up to run six days out of the week. 

A few hours later, Grassley shared a statement, which said Iowans encouraged Grassley to seek reelection when he was visiting the 99 counties. He said he is working to lower the cost of prescription drugs, give independent cattle producers a fair market, secure the border, protect the renewable fuel standard, and hold the government accountable to the people. 

“I’m working as hard as ever for the people of Iowa and there’s more work to do. In a time of crisis and polarization, Iowa needs strong, effective leadership,” he said. 

At 7 a.m. Grassley followed up with a short video, where he stood in front of a field during sunrise and said, “I’m running for reelection, it’s the right thing to do for Iowa.” 

Grassley received endorsements from Iowa Republicans Sen. Joni Ernst, Rep. Ashley Hinson, Reps. Randy Feenstra, and his son, Iowa House Speaker Pat Grassley. 

The National Republican Senatorial Committee also endorsed Grassley. 

“Chuck wakes up each morning – a bit earlier than most to run – thinking about how he can fight to ensure Iowa continues to be a great place for farmers, families, and job creators to succeed for generations. Chuck Grassley always puts Iowa first,” NRSC Chairman Rick Scott said. 

Former Democratic U.S. Representative Abby Finkenauer is Grassley’s most prominent challenger. She released a statement Friday morning in response to his announcement. 

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“Over his nearly five decades in Congress, Iowa has lost over 30,000 family farms, our jobs have been shipped overseas, and decade after decade our rural communities have been hollowed out with our young people leaving in droves as he stood on the sideline,” the statement said. “Meanwhile, Senator Grassley and his friends in the DC elite got richer while working families were left behind.”

The other Democrat running for the seat is Dave Muhlbauer, the former Vice Chairman of the Crawford County Board of Supervisors. 

Grassley also faces a Republican challenger in Sen. Jim Carlin, R-Sioux City, who announced he was running for the U.S. Senate seat in February. 

A poll from The Des Moines Register/Mediacom conducted Sept. 12-15 showed a majority of likely voters would support Grassley over Finkenauer, with 55 percent reporting they would support Grassley. 

Grassley is the second longest serving currently seated senator. During the Trump administration, he was president pro tempore from 2019-21. Grassley began in the U.S. Senate in 1981, after serving three terms in the U.S. House. He has represented Iowa in 24 consecutive U.S. Congresses. Before his career in Washington began, Grassley served in the Iowa House of Representatives from 1959-74.