(CNN) Voters who identify as independents are rarely actually independent -- and the ones who are tend to not care about politics, according to a new analysis by the Pew Research Center.
Independents are often seen as the best possibility for potential candidates to pick up votes outside their bases, but most independents actually "lean" toward one party or another, according to the analysis. Less than 10% of the population say they truly have no partisan lean.
In general, the number of Americans who consider themselves independents increased from 33% in 1994 to 38% in 2018.
Americans who identify as independents are more likely to lean toward the Democratic Party (17% of the total population) than toward the Republican Party (13% of the total population).
In 2018, just 7% of all Americans say they truly have no leaning toward either of the major parties. Those without a partisan lean -- true independents -- haven't increased as a share of the population, staying under or near 10% since Pew started tracking the question in 1994. Pew reports that those who do not lean toward a party are part of "a group that consistently expresses less interest in politics than partisan leaners" and "were less likely to say they had registered to vote and much less likely to say they voted."
Independents have started leaning more toward Democrats in the last five years, compared to being split with Republican-leaners in the past.
The study comes at a time when one possible candidate is making his sales pitch to the middle of the political spectrum, counting on what he believes to be a legion of moderates to back his potential candidacy.
Howard Schultz, the ex-CEO of Starbucks, who is a billionaire and potentially a 2020 third party candidate, thinks American politicians have become "too partisan" and that the majority of the country identifies as being somewhere in the middle of the political spectrum. That fuels Schultz's call for politics with less bickering and divisiveness.
But reaching those voters could be difficult, according to Pew.
Independents, regardless of which party they lean toward, are less likely to vote than those affiliated with either party.
In a Pew poll last fall, strong partisans were more likely to report that they were registered to vote and participated in the midterm elections, including 59% of Democrats and 61% of Republicans. But only about half of Democratic-leaning independents (48%) and Republican-leaning independents (54%) said they voted. A third of true independents reported voting in the midterm elections.
On issues that are often subject to partisan disagreement, independents usually agree with whatever party they tend to lean toward.
For example, on the border wall with Mexico, 87% of Republicans overall favor expanding the wall, while 92% of Democrats oppose it. Independents who lean Republican are still in favor (75%) and independents who lean toward Democrats are very strongly opposed (95%). Two-thirds of independents with no political leaning oppose the wall, showing a slight preference to the more liberal views.
Overall, just 34% of independents approve of the way Donald Trump is handling his presidency, but that masks widely divergent views among those independents who lean toward a party.
While Trump has very high approval among those who identify as Republicans (84% in 2018), independents who lean toward the GOP also strongly approve of him (69%).
On the other side of the ledger, Democrats and independents who lean toward Democrats are also strongly correlated: Seven percent of people who identify as Democrats approve of the job Trump is doing and 9% of independents who lean toward Democrats feel the same way.
These results are based on a Pew Research Center analysis of surveys of all adults conducted in 2019 and earlier. Results on Trump's approval rating are based on a compilation of 2018 surveys conducted, and results on the wall are based on a survey from January 9 through 14, 2019.