Source: Rasumussen

Emphasis Mine

Republicans and unaffiliated voters are more likely than Democrats to have changed candidates as a result of the 10 GOP and six Democratic presidential campaign debates. But most voters who have followed the debates are pretty much where they were before it all began. (To see survey question wording, click here.)

The survey of 1,000 Likely Voters was conducted on February 25 and 28, 2016 by Rasmussen Reports. The margin of sampling error is +/- 3 percentage points with a 95% level of confidence. Field work for all Rasmussen Reports surveys is conducted by Pulse Opinion Research, LLC. See methodology.

See:http://www.rasmussenreports.com/public_content/politics/elections/election_2016/gop_voters_unaffiliateds_more_influenced_by_debates_than_democrats_are