Larry J. Sabato is university professor of politics and director of the University of Virginia Center for Politics, which publishes the online, free Crystal Ball politics newsletter every Thursday, and a contributing editor at Politico Magazine. His most recent book is The Kennedy Half-Century: The Presidency, Assassination, and Lasting Legacy of John F. Kennedy. Kyle Kondik is managing editor of Sabato’s Crystal Ball, a nonpartisan political newsletter produced by the University of Virginia Center for Politics. His forthcoming book, The Bellwether: Why Ohio Picks the President, is scheduled for release next year by Ohio University Press. Geoffrey Skelley is associate editor at Sabato’s Crystal Ball.

Down-ballot races are increasingly decided by who wins the White House. To grasp this fact, it’s best to focus on two numbers: 6 percent and .781.

The first number is the total percentage of House districts that voted for different parties for president and for U.S. House in 2012. It was the lowest percentage in nearly a century. The second number is the correlation between the presidential results and the Senate race results in 2012. (Zero indicates no relationship, while one would indicate a perfect, exact relationship between two variables.) The correlation between presidential and Senate voting in 2012 was higher than it had been in more than half a century.


In other words, the presidential race looms very large down the ballot. And, as we examine the state of the Senate, House and gubernatorial races coming up this year and next, the presidential outcome may be especially important in the highest-profile category: the Senate.

#1. To win the Senate, win the White House

The key to Senate control in 2016 will be the state-by-state presidential results. If the GOP presidential ticket wins, even if by a hair, it will be exceptionally difficult for Democrats to take back the Senate. On the other hand, a Democratic squeaker for the presidency might not capture the Senate, but a victory of a couple percentage points may well do the trick.

Most analysts acknowledge that Democrats have a plausible but narrow path to a minimal Senate majority, requiring a net gain of four seats if a Democratic vice president is elected, or five seats if the GOP wins the White House. But this will be a heavy lift because Democrats need to capture the lion’s share of the small number of truly competitive Republican seats on 2016’s map (Florida, Illinois, New Hampshire, North Carolina, Ohio, Pennsylvania and Wisconsin). Moreover, Democrats have to hold their shaky seats in Colorado and Nevada. Other than Illinois, these are all states that should also be competitive in the race for the White House, which will make presidential coattails all the more important.

Because the route to a Democratic majority is difficult, the Republicans are still more likely to keep the majority than the Democrats are to grab it. At least a small net loss for the GOP is expected, though. Not losing any net seats probably requires the Republican nominee to not only win the presidency, but capture more than 300 electoral votes — something no Republican has done since George H.W. Bush in 1988.

#2. The year’s most important Senate primary

One reason Democrats have won Senate seats they should have lost in recent years is because the party has generally been able to select stronger candidates than Republicans in critical contests. Several Republican candidates, like Richard Mourdock (Ind.), Todd Akin (Mo.), Sharron Angle (Nev.), Ken Buck (Colo.) and Christine O’Donnell (Del.) kicked away winnable seats in 2010 and 2012. Democrats have had some duds of their own in recent years, but they will be saddled with their own Akin if Rep. Alan Grayson beats Rep. Patrick Murphy in the Florida Democratic Senate primary.

Democrats fear they cannot capture the Florida seat if the bomb-throwing Grayson wins, whereas they think they have a good shot with Murphy, a former Republican who has positioned himself as a centrist. Republicans understand this too, and some outside conservative groups have already run ads attacking Murphy to help Grayson, a tactic popularized by Sen. Claire McCaskill’s (D-Mo.) maneuvering to aid the weakest GOP primary candidate, Akin, in 2012. (It’s worth noting that the Republican primary in Florida is very much unsettled as well.)

There’s a larger question at work here, too. The old trope, popularized by Bill Clinton, is that Democrats fall in love while Republicans fall in line, but the opposite has been truer in down-ballot primaries over the past few cycles. A Grayson nomination, won by tarring Murphy as a faux Democrat, would suggest that the Democratic establishment could be having problems with party unity, just like the Republicans have, as President Barack Obama leaves the scene.

#3. Will any incumbents face primary trouble?

The old adage about there being only two ways for an incumbent to run for reelection — scared or unopposed — remains as apt as ever. But at this point in the 2016 cycle, few senators are trembling. In fact, it’s hard to identify a single senator who might fall victim to an intraparty challenge. The most common names bandied about are Sen. Lisa Murkowski, the Alaska Republican who won reelection in a write-in campaign after losing a 2010 primary, as well as Sens. John McCain (R-Ariz.) and Jerry Moran (R-Kan.). However, none of them have attracted a high-level challenger yet.





After the turbulence of 2010 and 2012, when three sitting Republican senators failed to win renomination, every Senate incumbent (on both sides) who sought renomination won it in 2014. But the topline success hides some creakiness, particularly among the Republicans. Sen. Thad Cochran (R-Miss.) came within inches of losing, and others, like Sens. Pat Roberts (R-Kan.) and Lamar Alexander (R-Tenn.) didn’t even clear 50 percent against weak challengers. It’s possible that the 2016 Senate incumbents will have an easier path to renomination, but there’s also discontent in the air, particularly on the Republican side, which should keep the incumbents on their toes.

On the House side, five representatives lost renomination in the 2014 cycle (this includes “kissing Congressman” Vance McAllister, who failed to advance out of Louisiana’s jungle primary). That total was slightly higher than other recent non-redistricting cycles: four lost renomination in the 2010 cycle, three in 2008, and two in both 2006 and 2004. Nonetheless, 387 of 392 incumbents seeking renomination in 2014 successfully advanced to the general election, so it wasn’t exactly an incumbent bloodbath. This far out, about the only thing we can say is that it’s likely that at least someone will lose renomination in the House: Going back to the 1974 cycle, there has always been at least one sitting representative who lost his or her party’s nomination.

#4. More retirements are coming

So far, six representatives and four senators have announced that they won’t be seeking reelection in 2016, a total of 10. This doesn’t include members who are running for other offices or those who have resigned from office during the 114th Congress. Based on Roll Call'’s handy “Casualty List,” history suggests that at least a few other members of Congress will also be leaving Capitol Hill by choice in the coming months: Since the 93rd Congress in 1973-1974, the lowest total number of retirements was 13 in the 1984 election cycle. Over the past 40 years, the average number of congressional retirements is about 29—close to 23 in the House and a little over six in the Senate.

Despite the historical average, it’s possible that there will not be any more Senate retirements. After all, during the 2014 cycle, every senator who decided to retire did so by March 2013, except for appointed Sen. John Walsh (D-Mont.), who was forced out under unusual circumstances. These early decisions make sense: Statewide campaigns are expensive, especially in competitive races, so many retirees opt to give their party and potential successors plenty of time to figure out plans for the next election. However, Sens. Ben Nelson (D-Neb.) and Olympia Snowe (R-Maine) announced their exits much later on in the 2012 cycle (December 2011 and February 2012, respectively), so perhaps another senator will decide against running again in 2016. Should only four senators retire, it would be the lowest number since the 2006 election cycle (also four).

On the House side, only two representatives had announced they weren’t running again by this time in the 2014 cycle. As 22 others eventually joined them, we can be confident that at least a few more members will hang up their spurs in the coming months.





#5. New candidates will emerge

There’s still plenty of time for candidates to surface in key races. Now-Sen. Cory Gardner (R-Colo.) didn’t announce his campaign until February 2014, and former Massachusetts Republican Sen. Scott Brown, who almost beat Democratic Sen. Jeanne Shaheen last year in New Hampshire, didn’t officially jump into that race until April. During the 2012 cycle, now-Sen. Heidi Heitkamp, a Democrat, didn’t enter the North Dakota Senate race until November 2011. Though some primaries were moved up this year on account of the presidential race, down-ballot filing deadlines are months away. That leaves plenty of time for both parties to shuffle their lineups, including in places where the parties lack top-tier challengers, such as Republicans in Colorado’s Senate race and Democrats in North Carolina’s.

#6. Could the House Republicans’ big majority actually get bigger?

Given that Republicans have their biggest House majority since the start of the Great Depression—247 seats—one might think that they are dramatically overextended in the House. Instead, it’s not out of the question that Republicans could make a tiny addition to their majority if they win the White House by a few percentage points.

The more likely outcome is a small Democratic gain regardless of the presidential result simply as a correction against the large Republican majority now. But Republicans are not nearly as overextended as Democrats were after the 2008 election, when they won 256 seats. In the subsequent 2010 midterm, Democrats were defending 48 seats won by John McCain in the previous presidential election, and they ended up losing 36 of them. By contrast, Republicans now hold just 26 seats that Obama won in 2012, and of those, Obama won only 14 by a greater margin than he won nationally in 2012. And some of those seats are held by entrenched GOP incumbents.

Since Democrats need to net 30 seats to win the House, Democrats reclaiming the majority isn’t likely unless they win the presidency in a landslide and put many Republican seats that now appear safe into play.

#7. Democrats on defense in gubernatorial races

Perhaps the biggest surprise of the 2014 midterms was that Republicans, despite having to defend 22 of 36 governorships, ended up building on their governorship total, going from 29 to 31.

Unfortunately for Democrats, they may have to wait until 2018 to cut into that GOP edge: Of 15 races being contested this year and next, Republicans are defending just six seats, while Democrats will try to hold on to nine seats, or half of all the 18 governorships they currently hold.

Of the three races being held this year, Republicans should easily hold Louisiana and Mississippi, while Democrats are struggling to defend their open seat in Kentucky. Though Kentucky businessman Matt Bevin is a weak Republican candidate who has struggled to reunite his party after his unsuccessful challenge to Senate Majority Leader Mitch McConnell in last year’s primary, his opponent, state Attorney General Jack Conway, a Democrat, does not have an enviable reputation as a campaigner and is burdened with Obama’s severe weakness in the Bluegrass State. We see Bevin as a tiny favorite, thanks to Obama’s unpopularity in the state, but this is a tight race.

Moving to next year, Democrats have good prospective candidates but face difficult holds in Missouri, West Virginia, and maybe Montana and Vermont. To make matters worse, New Hampshire could come into play if Gov. Maggie Hassan (D) decides to challenge Sen. Kelly Ayotte (R). Meanwhile, Democrats have a marquee pickup opportunity in North Carolina, which should be a very competitive election between Gov. Pat McCrory (R) and state Attorney General Roy Cooper (D). Beyond that, Democrats could have an outside shot against Gov. Mike Pence (R) in Indiana and at an open seat in North Dakota, although Sen. Heitkamp’s (D) decision to stay in the Senate makes the Republicans a strong favorite to hold the Flickertail State.

Ultimately, it’s more likely than not Republicans begin 2017 with more governorships than they hold now. But keep in mind that presidential coattails and other factors will undoubtedly affect some 2016 races in ways we cannot yet predict.

#8. The historic power of incumbency

In a large majority of elections, incumbency is a powerful, often dominant, factor. Historically, 75 percent of senators have won renomination and the general election; the success rate for House incumbents is about 90 percent. When looking only at the general election, the winning percentages rise to a little over 80 percent for senators and 94 percent for representatives. Gubernatorial incumbents have also been very formidable, with about three-fourths winning both renomination and the subsequent general election over the past 70 years.

The power of incumbency could be particularly pivotal in the 2016 Senate cycle, where there could be as many as 29 incumbents seeking reelection. Republicans are defending seven seats in states that Obama won in both 2008 and 2012 at the presidential level; six feature GOP incumbents (Marco Rubio’s presidential run opens up Florida). Although Iowa’s Chuck Grassley is effectively unbeatable, the others are likely to have tough reelection battles, particularly in Illinois and Wisconsin, the two most Democratic states of this group at the presidential level. But if Republican incumbents in states such as New Hampshire, Ohio, and Pennsylvania can hold on in a presidential cycle, it will be very difficult for Democrats to win back control of the upper chamber. And the lack of a Democratic incumbent in Nevada may boost Republican chances of winning one of the GOP’s few opportunities on the Senate map.

This summer’s election season has been dominated by Donald Trump and, to a lesser extent, other outsider presidential candidates like Ben Carson, Carly Fiorina and Bernie Sanders. We do think there is a generic desire for unscripted voices in American politics. But as the elections for president and other offices draw closer, history tells us that betting on the insiders over the outsiders in most contests is safer. Nothing better illustrates this than the consistent, towering success of incumbents of both parties in primaries and general elections.

***

This is the second of a two-part series updating both the race for the White House and the battle for Congress and leadership of the states. Part one, on the presidential race, is here.