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Outcome: Biden 306 EV (D+1.2% from toss-up), Senate 50 D (D+1.0%)
Nov 3 polls: Biden 342 EV (D+5.3%), Senate 50-55 D (D+3.9%), House control D+4.6%
Moneyball states: President AZ NE-2 NV, Senate MT ME AK, Legislatures KS TX NC

Optimizing Your Efforts in 2018: Part II, the Senate

August 2nd, 2018, 1:04am by Sam Wang

PEC High-Impact Races for 2018
In 2018, what’s a swing state? In many cases, it’s not the swing states that everyone focused on in 2016. How should you optimize your activism and donations? tl;dr: You can donate via the PEC ActBlue page (if you like Democrats) or the NRSC (if you like Republicans).

The reason for the difference from 2016 is obvious: this year’s big questions are not the Presidency, but who will control the House, the Senate, and governor’s mansions and legislatures. In some cases, the hot races are still in purple states (Nevada, Florida), where the statewide vote is closely divided. But just as often, maybe more so, regional factors matter.

For example, Indiana is strongly Republican in its Presidential voting, yet Senator Joe Donnelly (D) beat the eccentric Richard Mourdock (R) for a Senate seat six years ago in 2012, a somewhat-good year for Democrats. This year, Donnelly has a fighting chance to retain his seat. More broadly, current polls indicate six knife-edge Senate races: Nevada (D-Rosen v. R-Heller), North Dakota (D-Heitkamp v. R-Cramer), Missouri (D-McCaskill v. R-Hawley), Florida (D-Nelson v. R-Scott), Indiana (D-Donnelly v. R-Braun), and Tennessee (D-Bredesen v. R-Blackburn).

Not counting these races, Democrats are favored to end up with 46 seats, Republicans with 48. To take control, Democrats would have to win five out of the six knife-edge races. This is a tall order but not at all impossible. Races that look close at this point in the season tend to end up breaking in the same direction. For a probabilistic look, see David Byler’s Senate election model.

In addition, one might keep an eye on the Arizona and New Jersey races, though I think Democrats will likely win both. Conversely, Texas is still looking like a Republican hold, at least for now.


After you’re done donating, you can also look for a place to campaign near you. Door-to-door campaigning is by far the most effective known way of increasing turnout. Swing districts are all over the United States, as you can tell by looking at our 2018 Competitive District Finder.

Tags: 2018 Election · Senate

6 Comments so far ↓

  • John White

    Hi Sam. As a consistent small donor since 2008, I am overwhelmed by spam calls from liberal candidates and organizations. Sadly, it all started the week of my first donation to Hillary in 2016, whose campaign seems to have sold me out just as this phenomenon was going viral. Hiya and other call blockers help, but the political organizations are not above changing their numbers (or spoofing them) to avoid detection, and IOS does not have great tools to combat this plague.

    Any advice, short of changing my number? I’d be more likely to donate if I could be ensured some peace.

    If and when you are in Boston, let me know. I’d love to see you.

    Take care,

    • Sam Wang

      Hi, John! I don’t have any good advice for you, though…hmmm…

      One solution that occurs to me is to give out the number of the general switchboard at your university. Presumably the first line of defense there is an automated system for getting to your name. If anyone has legitimate business, they can still reach you.

      It would be grand to see you sometime!

    • LondonYoung

      Shifting the burden of filtering one’s political calls to your employer is a crime in many industries.

      At banks you may not use your office number for any political purposes.

    • Sam Wang

      John is in the academic sector. I am pretty sure we are not bound by the rule you describe.

  • Freeman Ng

    Shouldn’t IN be replaced by TX now on the PEC ActBlue page? (

    I linked to that page from a blog post I made in August ( and “boosted” into a Facebook ad with a fairly big budget, but now, I’m planning to boost the post again, and would like to be able to point people to a more optimzed action.

    Or should IN still be there and TX not be added?

    Thanks for any clarification or correction you can make.

    • Sam Wang

      September polls are:

      Indiana (n=2) D+0.5% so that has to stay

      Texas (n=5) R+3% which is arguable but I’m not ready to do that quite yet, since it could go back in Cruz’s direction. Plus O’Rourke is hardly underfunded. As inspiring as O’Rourke is, I think there is some wishful thinking by Democrats there.

      Thank you for linking!


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