Candidates, campaigns and coattails: the effect this year's wild race for the White House will have on state legislative contests is difficult to predict.

• Author: Diorio, Daniel
• Position: ELECTIONS 2016 - Cover story

For the more than 10,000 candidates seeking state legislative seats this year, observing the volatile race for the White House may feel a bit like watching an investment rise and fall in the stock market. Investors have relatively little control over how an individual stock performs, yet its performance can have a huge effect on their financial futures.

Likewise, legislators have little control over who becomes their party's presidential nominee yet the results can have a profound effect on their political futures.

Presidential candidates continue to influence voters' decisions all the way down the ticket. Since 1900, in 21 of the previous 29 presidential years, the party winning the White House has also gained seats in state legislatures. This "coattail effect" averages a gain of 129 legislative seats.

The campaign taking the White House typically succeeds because of its superior strategy, keen organization and ability to generate the most enthusiasm and commitment from voters. And it most certainly knows how to win the get-out-the-vote effort. But with this year's election unfolding like no other in modern history, the results are a bit more unpredictable.

"Citizens have the choice between the two most unpopular candidates ever," veteran journalist Mara Liasson told lawmakers at NCSL's Legislative Summit in August. How will that affect their voting?

The success of Donald Trump in winning the GOP nomination surprised everyone save his most ardent supporters. His unorthodox campaign has contrasted starkly with that of Democratic standard-bearer Hillary Clinton, who has appeared overly cautious, as if taking her cue straight from a "How to Run a Campaign" textbook.

The voters' choice of who serves as the next president--whether Republican or Democrat--will play a role in determining the victors of the state races as well, especially given that recent studies show an upswing in straight-ticket voting. But exactly how much influence this year's presidential nominees will have is a big unknown.

High Stakes for States

Even though the presidential race receives all the attention, the fact is, who wins control of legislatures and governorships will have a greater direct impact on the day-to-day lives of Americans than who occupies the White House and the halls of Congress.

State legislative elections are as important as ever. On Election Day, voters will determine the winners of 5,917 seats in 86 chambers in 44 states. That's more than 80 percent...