The news for Republicans this week hasn’t been good. But if the headlines augur a blue wave in November, the polling has been less consistent.
In the aftermath of Paul Manafort’s conviction and Michael Cohen’s plea deal, the polling outlook for Republicans in Wisconsin actually improved (though the surveys were conducted before the latest developments for these two former associates of President Trump).
Gov. Scott Walker has been trailing in his bid for a third term, after winning a recall election between his 2010 and 2014 races. Then the respected Marquette poll came out this week showing Walker tied with Democratic nominee Tony Evers at 46 percent apiece.
Sen. Tammy Baldwin, D-Wis., is one of the ten Democratic senators running for re-election in a Trump-won state this year, but she hadn’t been considered especially vulnerable. She led by 17 points in a July NBC News/Marist poll and 14 in an Emerson survey later that month.
Marquette, however, had Baldwin ahead by just two points. She took 49 percent of the vote — just a tick under the 50 percent threshold of comfort for incumbents — to 47 percent for newly minted Republican nominee Leah Vukmir.
In New Jersey, Quinnipiac — a pollster that hasn’t produced a lot of encouraging results for Republicans this election cycle — found incumbent Democratic Sen. Robert Menendez leading by just 6 points and well below 50 percent. Menendez took 43 percent to Republican challenger Bob Hugin’s 37 percent.
Generic congressional ballot polling, which tests which party respondents prefer to see in control of Congress, has been inconsistent all year, though Democrats have generally led. Just this week, Rasmussen Reports has shown the two parties tied, Fox News has had Democrats leading by 11, Monmouth has had Democrats up by 5 and Reuters/Ipsos gives Democrats a 4-point lead.
The RealClearPolitics polling average shows Democrats leading by 6.6 points. FiveThirtyEight’s average gives the opposition party a 7.8-point edge, giving them a better chance of retaking the House, something the forecasting website gives them a 72 percent chance of doing to the Republicans’ 28 percent odds of holding the majority.
Different polling firms employ different models, with various assumptions about who is going to turn out, and even polling averages can be skewed by which company’s surveys have come out most recently.
“Credible national polls these days are coming out from people using online panels, using traditional live interviews sampled using random digit dialing (RDD), and using live interviews sampled off of the voter file,” Republican pollster Chris Wilson told the Washington Examiner in an email exchange. “In addition, there are IVR (automated voice) polls that either supplement their landline samples with online or some other method.”
“In general, the RDD polls lean Democratic because they over-represent people who aren’t actually likely voters (and may not even be registered),” Wilson added. “The voter file samples can vary depending on what vote history they use to sample — a pollster sampling using 2010 and 2014 as their base is probably too Republican this year, but one using 2016 may be overstating independents.”
Even small differences can alter public perceptions. Republicans thought the polls underestimated their support in the 2012 presidential election and were wrong. They thought the same thing in 2016 and were closer to the mark, especially in the states where Trump pierced the “blue wall.”
“I never believed in the ‘hidden Trump voter’ theory before,” said one GOP operative close to the White House. “I believe in it now.” But it is not clear those voters will turn out for down-ballot Republicans in the midterm elections this year without Trump running.
“In June, we had the generic ballot tied at 44,” John McLaughlin, a Republican pollster who has worked for Trump, told the Washington Examiner in a telephone interview. “July we had the Democrats at 46, the Republicans at 42. We model it after 2016 turnout, where there’s more Democrats than Republicans, but not like some of these polls that have 10-12 points more Democrats.”
“So we’re seeing a close race right now,” McLaughlin continued, “and the Republicans have a definitely have a shot … They’re gonna pick up Senate seats, the question is how many. And the House, they can hold the House, but they have to create an agenda so they’ll be able to nationalize it.”
McLaughlin noted the polling that went into creating the Contract with America in 1994, when Republicans took Congress in President Bill Clinton’s first midterm election. “Right now, the president has an agenda and where the Republicans are lagging is that where the president’s job approval has been going up, the Republicans in the Congress, their numbers aren’t going up as much.”
“Not a simple answer,” said a third pollster.
There isn’t a simple storyline of encouraging poll numbers for Republicans, either. Sen. Bob Casey, D-Pa., enjoyed a 15-point lead over Trump-backed challenger Lou Barletta in an NBC/Marist survey out this week. The same firm had Sen. Ted Cruz, R-Texas, up by 4 over Democratic opponent Beto O’Rouke.
“There are a couple of polls that clearly have a partisan bent,” said Wilson, who has polled for Cruz but was referring to the generic ballot rather than that particular race. “Rasmussen on the Right and Public Policy Polling on the Left are the two most notorious for being outliers in one direction or the other based on the assumptions they include about partisanship of the electorate.”
Subtle differences matter. Republicans could hold the House with a 4-point Democratic lead. They probably can’t withstand an 11-point Democratic advantage.
“There are also some smaller decisions that individual pollsters make, such as the order of their questions,” Wilson added. “Asking the generic ballot after questions about Trump’s job performance and/or Congress’s job performance, for example, can lead to slightly different results than if you asked the generic ballot first.”
Next thing to watch: the numbers that come out after the Manafort, Cohen, and Rep. Duncan Hunter, R-Calif., news has fully set in.
