13 September 2018 — 1132 mdt

538.com forecasts high probability of Tester win

The forecasts for the U.S. Senate released yesterday by Nate Silver at 538.com will gladden the hearts of Montana’s Democrats. All of Silver’s forecasts for Montana give high odds that incumbent Democrat Sen. Jon Tester will be elected to a third term.

I’m not as optimistic, and rate the election a toss-up. Although a 14 June Gravis poll reported Tester was up seven points, that lead declined to three points in a Remington Research poll conducted after President Trump’s visit to Great Falls. A partisan poll conducted by WPA Research on 20–22 August put Rosendale three points ahead. With the exception of the Survey Monkey polls conducted for Axios (more on that in a moment), those are the only publicly available polls.

The Survey Monkey polls, conducted 11 June through 2 July, report Tester leading by 10–13 points. FiveThirtyEight gives the Survey Monkey polls a “D-” rating, and I think that’s charitable. I could find no information on how the Survey Monkey’s sample was taken or weighted.

Tester has two advantages, incumbency and a pedestrian opponent. His disadvantages? Running in a midterm election and partially hitching his star to Trump’s.

Tester won his first election in 2006, a throw out the bums midterm with extraordinarily high voter turnout. It’s possible the 2018 midterm will be another high turnout election in which a lot of Republican incumbents get the heave-ho from the voters. If that happens, Tester’s in good shape. If the turnout is lower than in 2006, he could be in trouble.

His strategy of emphasizing his ability to get his legislation signed by Trump is risky. Trump can respond “Yes, I did sign some of his bills, but if you send Matt Rosendale to the Senate there’ll be more good bills that I can sign.” That invites voters who prefer a real Republican to an election year pretend Republican to vote for Rosendale.

The Libertarian

Both of Tester’s victories were by plurality. In 2006, he won the two-party vote 50.4 to 49.6 percent over incumbent Republican Conrad Burns, but received only 49.2 percent of the overall vote. Six years later, Tester won the two-party vote over challenger Rep. Denny Rehberg 52 to 48 percent, but received only 48.6 percent of the overall vote. In both elections, the Libertarian candidate received more votes than Tester’s margin over the Republican.

Montana’s Republicans, and many if not most of Montana’s Democrats, are convinced that the Libertarian vote robbed the Republican of victory. At one time, I found that theory convincing, but I now approach it with considerable skepticism.

The theory assumes that if the Libertarian had not been on the ballot, the people who would have voted for him would would have instead voted for the Republican. That premise can be true, but there’s no reason to suppose it’s true in all or even most cases. In 2012, for example, the voters who marked their ballots for Libertarian Dan Cox knew they were denying their vote to Denny Rehberg. Had Cox not been on the ballot, these voters had several choices:

Not voting.
Voting for Rehberg.
Voting for Tester.
Casting a write-in vote.

Both Cox, and Stan Jones in 2006, allowed Republicans who had no confidence in Burns or Rehberg, who couldn’t stand the thought of not voting, but couldn’t abide the thought of voting for a Democrat, a way to discharge their civic duty without violating their principles. In 2018, Rick Breckenridge provides the same safety valve.

The Trump effect

President Trump has visited Montana twice, once in July, once in September, to campaign for Rosendale. He would not have made the second trip had not polling suggested his presence in Montana helped Rosendale.

In mid-July, Trump still had a net favorable rating of five percent. Although his favorability is declining on a nationwide basis, it could be holding in Montana. If Trump’s popularity holds, and if Rosendale becomes a proxy for Trump, that augurs ill for Tester.

I suspect there are even odds that Trump will return to Montana in early October, and that Vice President Pence may visit the state again as well.