Five Senate Republicans said they would not pursue another term, creating the potential for more competitive races, especially in the undecided states of Pennsylvania, North Carolina and Ohio.
The Senate pro temp emeritus was considered particularly difficult to win. In his most recent competition in 2016, Grassley won 60 percent of the vote, beating Democratic nominee Patty Judge by 24 points.
The Des Moines Register / Mediacom poll showed Grassley’s favorability index at 48 percent, stable since recent surveys dating back to June. However, compared to previous Iowa polls in 1998, its favorability in the state is in a slow but steady decline, dropping 12 points since 2019.
The Des Moines Register / Mediacom survey of 775 Iowa adults was conducted from March 7 to 10 and had a margin of error of plus or minus 3.5 percentage points.