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Sen. Chuck Grassley (R-Iowa) may be on the verge of overstaying his welcome. Grassley, 87, hasn't announced whether he plans to seek an eighth term in 2022, but a new Des Moines Register/Mediacom Iowa poll suggests he'd face an uphill battle if he does decide to run, the Register reported Sunday. The survey, conducted by widely respected Iowa pollster J. Ann Seltzer, found that only 27 percent of likely voters would re-elect Grassley if the election were today; 64 percent said they think it's time for someone else to occupy the seat Grassley has occupied since 1981.

Iowans generally have a positive opinion of their senior senator — his favorability rating is 50 percent, with 37 percent having an unfavorable view — but Grassley's job approval rating has slid to 45 percent, his lowest approval number since 1982, the Register reports. "Grassley's approval rating has occasionally hit the 80 percent threshold during that time."

"Given that we're talking about Chuck Grassley and the ratings he used to garner, that is a 'wow,'" said Selzer, president of Selzer & Co.

By party affiliation, 51 percent of Republicans, 7 percent of Democrats, and 23 percent of independents say they would vote for Grassley if the election were today, the poll found. "Chuck Grassley has had a long and mostly good run, but most Iowa voters appear ready to move on, and his ratings reflect waning interest," Selzer said. This is the first time her Iowa Poll has asked about re-electing Grassley this far ahead of the election, because his "stellar poll numbers" conveyed "a certain invincibility," she explained. "Well, it appears he is now vincible."

Grassley is the second-longest-serving sitting senator, after Sen. Patrick Leahy (D-Vt.), and the second oldest, being a few months younger than Sen. Dianne Feinstein (D-Calif.). If re-elected, he would be 95 at the end of his next term. 

The Iowa Poll interviewed 807 Iowa adults, 630 of them deemed likely voters in the 2022 midterms, June 13-16 by landline and cellphone. The margin of error is ±3.5 percentage points for the full sample ±3.9 points for the likely voters.