Many Republicans will choose "some Republican governor" over Clinton no matter what. But if national elections are swung by independent voters (who may or may not exist in practice, but that's another story) we can't really know if independent respondents in the CNN poll are picking Clinton because they like her, or because they're more familiar with her.
Research suggests that when voters don't know much about candidates in a given race, name recognition sways electoral choices. In 2013, researchers at Vanderbilt University tested this theory in an experiment involving subliminal messages and a fake election between two fictional men: Mike Williams and Ben Griffin.
Before the mock election, participants in the experiment saw letters and words flash by in rapid succession on a computer screen. In this flurry of words, half the participants saw the name "Griffin." But they didn't realize they saw it: The name flashed on screen for a total of 40 milliseconds. That's .04 seconds, barely enough time to record a thought. Psychologists call this priming, a process by which small, subtle cues can change future behavior.
Then, came the test, a simple question: "Imagine two candidates are running for political office: Mike Williams and Ben Griffin. If you were eligible to vote in this election, for which candidate would you vote?" Participants were not given any further information about the candidates, like party affiliation.
For those who had seen the name "Griffin" flash on screen for barely an instant, "Griffin" had a 5-point advantage at the ballot box. "Name recognition provides a sense of viability," says Cindy Kam, a coauthor of the study. "In cases where people have not heard of a challenger, then it's very difficult to imagine that challenger could be viable."
The computer scenario actually isn't all that contrived: consider the amount of time a person spends looking a campaign yard sign while breezing by in a car.
Kam says it's unlikely that name recognition is a factor in general elections. Come Election Day, both the Democratic and Republican candidates are household names. But it is possible, she says, that name recognition affects voter sentiment in early polls.
"These polls that are happening even a year before anything, this is a low-information context," Kam says. "This is where name recognition matters."
In the same poll, CNN also asked Republicans and Democrats about their respective primaries. It found that Bush is winning the GOP primary race, with 16 percent of Republican respondents saying they would vote for him. The runner-up is Walker, with 13 percent. The poll's margin of error is 4.5 percentage points. But if Bush is the front-runner in the poll, is it because he's truly more well-liked, or is it because more people know who he is? After all, 86 percent of respondents recognized Bush, versus the 52 percent who recognized Walker. The effects of name recognition may be stronger in party primary polls than in general-elections poll because respondents aren't choosing between parties, just names.