Sean Trende of Real Clear Politics has become one of the nation's top political analysts. Sean and his colleague David Byler have just released a new tool for analyzing the 2018 U.S. Senate elections.
Drawing upon recent history, they have identified a few key factors that will determine control of the Senate -- the president's job approval rating, which incumbents are running for re-election, and whether either party has nominated an especially problematic candidate. They let you make your own assumptions, push a button, and a computer program runs 10,000 data-driven simulations to determine a range of possible outcomes.
Some political number geeks will have a great time playing with this toy and testing all sorts of assumptions. But, for more normal people, the primary value of this tool is to make clear just how unlikely it is that the Democrats will win control of the Senate in 2018.
The core problem for Chuck Schumer's party is the map. Of the 33 seats up for re-election in 2018, only eight are currently held by Republicans. Since the Democrats need a net gain of three seats to win Senate control, they must successfully defend 25 of their own seats and then pick up three of the eight GOP seats.
This long shot for the Democrats is even more difficult than it seems at first glance. Only two of the Republican Senate seats are in decently competitive states (Arizona and Nevada). And, many Democratic Senators are running for re-election in Republican leaning states such as Montana, North Dakota, West Virginia and Indiana.
Still, some Democrats are clinging to the belief that Donald Trump will be so unpopular by 2018 that the Republican Senate majority will be at risk. This is where the Trende/Byler tool comes into play.
I ran a series of simulations using the Real Clear Politics default assumptions about everything except the president's job approval rating.
If the president's job approval rating slips a bit further and is hovering around 40 percent on election day 2018, the most likely projected outcome is that nothing will change. The Republicans will still have 52 Senate seats while the Democrats will hold 48. Even with the president enduring such low approval ratings, the Democrats would have less than a two percent chance of winning Senate control. And, in that scenario, 32 percent of the simulations show the Republicans gaining Senate seats despite the unpopular president.
Perhaps the most sobering finding for Democrats is what would happen if President Trump's Job Approval fell all the way to 35 percent. Some Democrats may see that as a likely outcome just as some Republicans always assumed President Obama's numbers would get that low or lower. But in today's hyper-partisan tribal politics, it would take a lot for Trump's numbers to tumble that far. And, even if they did, the Democrats would still have only a 21 percent chance of winning the Senate.
Obviously, the midterms are a long way off and much can happen. And, as Trende and Byler note, the current president is not your typical politician, so the old rules may not apply. But the interactive tool released on Real Clear Politics makes clear just how much of an uphill climb the Democrats have in the 2018 Senate elections.