Looking ahead to November, the presidential race could decide more than just who the next president is. It could also determine which party controls the Senate-House or or even your state’s legislature. And that’s because of something in political science, calls the “coattail effect:,” which is when the popularity of the candidate at the top of the ticket — we’re most interested in, the presidential coattails — it increases the fortunes of candidates from the same party, the lower down on the ballot.
Political science has long tried to measure just how big of an effect this is, and most research does suggest that the down-ballot candidates gain at least a few votes, thanks to the performance of the candidate at the top of the ticket, but estimates vary as to the actual size of the coattail effect. For instance, in the House races, where we have the most data, some studies have found from anywhere on the 0.2-point to 0.5 point bump for the House, applying for every 1-point increase on the the presidential candidate has experience in the vote-share. That may not sound much like, but if a candidate in a competitive House seat you are attracted 48 percent of the vote in the by herself, to the strong performance by the same party”s presidential candidate could boost in her vote share, just enough that she will clear the 50 percent mark, and wins.
And as the chart below shows, the margins in the presidential House, and races jo tend to move together. This alone doesn’t prove the existence of a coattail effect, but it does show how closely these votes are connected. For instance, in 2004, President George W. Bush won reelection by 2.5 points, while the GOP won the national House vote by 2.6 points. Of course, it’s not always so symmetrical in 1996, President Bill Clinton won reelection by 8.5 points, but Democrats won the House vote by only 0.3 points. Overall, though, that, from 1992 to 2016, ” we found a strong correlation (0.655) between the ni margins for the presidential House, and races.
James Campbell, a political scientist at SUNY Buffalo, who has studied the presidential coattail effect in congressional races, found that in a typical presidential election year, and, from, to 1868 to 1988, the party picked up an average of two to three House seats because of the coattail effect. And, from election to election, and the effect might be even stronger. Political scientists of the Franco-Mattei and Graham Glasgow looked at at at at at the House contests from 1976 to 2000 and found that a strong presidential candidate could swing to almost 10 percent of contested House races.
There’s been less work on the coattail effect in the Senate because, unlike the House, it doesn’t have truly national elections. Still, in a 1991 study by martin Campbell and Joe Sumners found that the Senate contenders got an average boost of only 0.2 points per 1 percent increase in the vote for the same party”s presidential candidate between 1972 and 1988, which they concluded affected the outcomes in two to three events per cycle. Again, that might not sound much like, but that’s enough to flip the chamber, if it is closely divided — as it is right now. Additionally, the non-presidential study of the coattail effect, by Marc Meredith, a political scientist at the University of Pennsylvania, found that gubernatorial candidates improved, the votes of the lower-office contenders from their party and by 0.1 to 0.2 points.
Estimating the coattail effect in a given cycle is a person, though that there’s no real consensus about its size. The studies are negative after treatment, we all have different estimates, and one study of House contests from 1916 to 2006 and by the political scientist Ray Fair found that House candidates’ vote shares were boosted from anywhere, 0.8 points to -0.7 points, which calls into question how much we can really generalize about the positive effect of coattails.
The experts I spoke with were unsure of the coattails’ you need effect because of the other brazil, that can affect voting, like incumbency or the state of the economy. For instance, some studies have found the coattail effect is notably stronger in the open-seat contests, where no incumbent is running for reelection. And according to Campbell, something like the economy, you live with the electoral consequences than the coattail effect by itself, but the effect is often a by-product of those big-picture-election conditions. “If the economy brings some more Republicans out to vote for Trump, that’s going to help Republicans as they’re going to be there to cast your vote in the congressional races,” said Campbell.
Experts argue that where we really see the coattail effect is in the seat among the party”s base. The way [the top of the ticket is] going to benefit the down-ticket candidates on the world wide web is getting by members of that party to show up to vote,” said Meredith. This is especially true in our polarized era, that has high rates of straight-ticket voting. “For every 10 the partisan-to-get-out to vote for a presidential candidate, you’re probably getting eight or nine of them for the voting [same party’s] House, apply,” added Campbell.
But one reason why the coattail effect, it isn’t more pronounced is the countervailing at at at at at work force known as “balancing,” which is when someone votes against the party they think will win the presidency in the down-ballot races. Looking at elections from 1948 to 2012, a political scientist As Robert Erikson of Columbia University, found that, if a presidential candidate was heavily favored to win, highly engaged, moderate voters often cast House votes for the other party, an “ideological hedge” of sorts. It’s true that only a relatively small number of voters do this, and split-ticket voting for president and Congress you have generally declined in recent yearsbut enough voters still do this, that it can make a difference in the House races.
Consider the 2016 election. Some high-information voters to split their tickets, in the Senate House, and the races, because the most signs — whether it was a the betting markets or election forecasts — pointed to Hillary Clinton’s winning the presidency. And that’s probably helped the GOP to hold on to some districts that Clinton carried, particularly highly educated seats in the suburbs of major metropolitan areas, such as the Virginia”s 10th District, outside of Washington, D. C., and Minnesota”s 3rd District, outside Minneapolis.
That said, there aren’t many of these the crossover seatsor seats where the party that wins-it-in-the-House doesn’t carry it at the presidential level. The election of 2016 had the 35, such as for House seat, which was up only very slightly from 2012, when there were just 26 in the split results. And in the Senate, every seat went to is the same party that won the state at the presidential level.
Part of the reason there aren’t more crossover from seat is that the coattail effect generally plays a larger role than balancing. Los angeles even told me that he didn’t think balancing was enough by itself to make it difficult for the party with a clear lead in the presidential polls. The os update is that it is worth considering the potential upside of the coattail effect in the year 2020, don’t be surprised to hear Trump and former Vice-President, Joe Biden emphasize their ability to help their party’s ticket in the election campaign heats up. For instance, He has already begun to the “campaign” on the idea if he can help Democrats put more Senate seats in play and protect the party’House majority. And for their part, Republicans are already showing signs of concern that’s Trump”s handling of the coronavirus pandemic, and the state of the economy could harm Republicans in down-ballot races, and will jeopardize the party”s Senate majority.
It’s unlikely that Trump or Biden”s candidacy will, in the make-up all the difference in these key races, but this is some down-ballot candidates, it might not hurt to grab a hold of their presidential candidate”s coattails.
