So who will be in charge in Washington next year? Right now, The Cook Political Report is forecasting that the most likely midterm-election outcome in the House is Democrats picking up between 20 and 40 seats, with a 30-seat net gain a plausible guess. A Democratic gain of 23 seats is the minimum necessary for the party to gain the speaker’s gavel, and a haul of more than 40 seats is likelier than a gain of fewer than 20 seats, a wash, or a GOP gain.

Nate Silver and his FiveThirtyEight team released three House models this past week giving Democrats between a 69 and 75 percent chance of capturing control of the House, saying the most likely outcome is Democrats picking up between 32 and 35 seats. A number of academic models developed by some of the most-esteemed political scientists in the business will be released in the coming weeks showing Democratic gains of as few as 27 to as many as 44 seats.

Unless Democrats score net House gains of 46 seats or more, their majority would be smaller than the current GOP majority. If Republicans retain a majority, it will certainly be smaller than it is today. Anything short of a Democratic gain of 60 or more seats means that it would a real challenge for House Democrats to get much out of the chamber (a 60-plus seat gain for Democrats is possible, but very unlikely given current congressional-district boundaries and natural-population patterns).

There is much more uncertainty in the Senate: While the political environment this year obviously favors Democrats, we are looking at the most lopsided partisan Senate map in history. Regular readers of this column know that Democrats have 26 seats up, to just nine for Republicans. Ten Democratic seats are up in states won by President Trump, five in states he won by 19 points or more, while there is just one GOP seat in a state carried by Hillary Clinton. This really is a Democratic tidal wave crashing up against a Republican seawall.

Republicans desperately hope that geography will trump a challenging political environment, pointing to the recent Pew Research Center study showing that in regular and special Senate elections held since 2013, 69 out of 73 were won by the party carrying that state in the most recent presidential election. Every single Senate race in 2016 was won by the same party that prevailed in presidential balloting there.

Given the map, and keeping in mind the Pew study, a good case can be made that Republicans pick up at least one and as many as three seats, resulting in a GOP Senate majority of 52-54 seats. Conversely, giving Senate Democrats every conceivable break—holding all 26 of their own seats, winning the open seats in Arizona and Tennessee, and knocking off incumbents Dean Heller in Nevada (quite plausible) and Ted Cruz in Texas (tougher, but possible)—a Democratic-led 53-47 chamber is as far as it could possibly go. The reality is that no party is going to exceed 53 or 54 seats, making for a tough legislative sled given the rules and practices of the Senate.

So what could be the anticipated policy consequences of the most-likely election scenarios? Keeping in mind that it is almost always easier to stop something than to pass something, we should first expect legislative paralysis to get even worse than today. Even if Democrats win big in the House, the odds are good that the Senate will still be in Republican hands; even the best-case scenario for Democrats is a tiny Senate majority for them—and President Trump will still wield the veto pen.

Governing costs money, and with soaring budget deficits and the federal debt looking increasingly ominous, spending money, whether in the form of appropriations or more tax cuts, will be very difficult, further dimming the chances for real legislative results.

Should a big blue wave actually materialize, the temptation will be for Democratic House or Senate majorities, unable to enact a legislative agenda or to escape the presidential veto pen, to focus their attention on subpoenas and impeachment. Some might say this would show Trump what a real witch hunt might look like, or it would return the torment that Republican majorities inflicted on the Obama administration. Either way, it will lead to few if any true legislative accomplishments.

As a result of all of this, look for power to continue to flow down Pennsylvania Avenue from Capitol Hill and toward the White House, Cabinet departments, and regulatory agencies and commissions. Congress’s inability or unwillingness to effectively deal with many of our toughest problems has unquestionably created a vacuum, one filled on one level by the executive branch and on another by governors and state legislatures. Obama and Trump both pursued far more aggressive use of executive-branch authority at the expense of Congress, exceeding previous presidents and, arguably, the intentions of the Founding Fathers.

Increasingly the courts are being pulled into the fray, refereeing disputes over executive authority. Some argue that while the Founding Fathers intended for the judicial branch to be the least influential of the three, it is now becoming more powerful, with Congress becoming less. This is where the moves by Trump and Senate Majority Leader Mitch McConnell have become especially important, putting more staunch conservatives on the bench.

Humility is always necessary with election forecasting; after all, we are talking about human behavior and politics is a dynamic, not static, exercise. Events can alter the trajectory of an election. Voters will settle many of these questions in November, but it’s hard to see a scenario occurring that does not suggest the likelihood of legislative paralysis.

This story was originally published on on August 21, 2018

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