Iowa State Sen. Joni Ernst is outpacing four rivals for the Republican U.S. Senate nomination on the eve of the June 3 Iowa primary, according to a Suffolk University bellwether ID poll of tightly screened Republican primary voters in Black Hawk, Boone and Washington counties.

Montana Democratic primary for U.S. Senate

Meanwhile, in the Montana Democratic primary for U.S. Senate, recently appointed Sen. John Walsh leads the other two Democratic candidates in all three primary bellwether counties—Cascade, Glacier, and Lake counties. Walsh led former Lieutenant Governor John Bohlinger and rancher Dirk Adams by between 24 percent and 30 percent, although the undecided figure fluctuated wildly from a low of 19 percent in Cascade County to a high of 40 percent in Lake County. The Democratic nominee likely will face Republican Congressman Steve Daines in November to fill the seat vacated by Senator Max Baucus, who was appointed ambassador to China earlier this year. Susan Cundiff and State Rep. Champ Edmunds also are running for the GOP nomination.

Five-way GOP race in Iowa

Ernst led all four of her Republican opponents—businessmen Mark Jacobs and Scott Schaben, radio show host Sam Clovis and former U.S. attorney Matt Whitaker—by between 20 and 34 percent. The November election will pit the Republican nominee against Democratic Congressman Bruce Braley, who is unopposed in the Democratic primary, as well as independent and third-party candidates also vying for the Senate seat.

“Joni Ernst has caught the imagination of Republican voters and is extending and accelerating her advantage over her GOP opponents,” said David Paleologos, director of the Suffolk University Political Research Center in Boston. “In the April statewide poll, Ernst had just overtaken Mark Jacobs, and it was close at that point. Now, the bellwethers are confirming her improved standing and solid strength in the Republican primary.”

On April 9, Suffolk University released an Iowa statewide poll that was the first to show Ernst leading all of her opponents in the Republican Primary for U.S. Senate. Since then, the five public polls taken in Iowa have shown Ernst leading by various margins.

Iowa Republican gubernatorial primary

Gov. Branstad also will appear on tomorrow’s GOP ballot, and all indicators point to a nearly four-to-one advantage for his party’s nomination. Branstad led Republican challenger Tom Hoefling by 50 percent to 64 percent in all three bellwethers.

Bellwether success

A bellwether is an area of a state that closely mirrors a statewide electoral outcome using similar election types from previous elections and other data. Paleologos’s bellwether model has been used nationally since 2002 and is 85 percent accurate in predicting winners, but it is not designed to predict margins of victory. All bellwether analyses carry a margin of error similar to a statewide poll.

Republican primary data from similar elections in the past show that all three Iowa counties—Black Hawk, Boone, and Washington—are good indicators of Republican primary sentiment. For example, in the 2010 Republican Primary, all three counties reflected the statewide order of finish (1-2-3) exactly and were within 5 percent of the statewide vote margin for each of the three GOP candidates running for governor that year: Terry Branstad (50 percent), Bob Vander Plaats (41 percent), and Rod Roberts (9 percent).

The Suffolk University Political Research Center has been 100 percent accurate to date in polls where three bellwethers have been chosen for a particular race and all three bellwethers have shown the same winner. This is the first time Suffolk University has tested bellwethers in the state of Montana.

Methodology

Using party primary voter lists, the bellwether IDs were called using a tight screen. All respondents indicated that they were likely to vote in the state’s respective primaries or had already voted. All other respondents were screened out. The field was conducted Tuesday, May 27 through Friday, May 30, 2014. The margin of error for is +/-5.65 percent at a 95 percent level of confidence. Bellwethers are designed to predict winners, not margins or runners-up. Results are posted on the Suffolk University Political Research Center Web site. For more information, contact David Paleologos at 781-290-9310.