(CNN) Positive references to President Donald Trump in June and July congressional campaign ads bested even those of President George W. Bush -- whose approval ratings after 9/11 were some of the highest ever seen -- at the same point in 2002, according to a new analysis.

Bush was mentioned positively in about 14% of the 2002 midterm campaign ads over that two-month period, compared with Trump's 15% in 2018.

Michael Franz, co-director of the Wesleyan Media Project , said in the release of the data Wednesday, "The president's party tends to lose seats in midterm elections, and so typically candidates from the party tend to avoid tying themselves to the incumbent while opponent partisans typically go on the attack."

"It is really striking," Franz added, that Republicans are overwhelmingly embracing Trump and are "very rarely criticizing him. It suggests that many Republican primary voters are still very enthusiastic about the President, in a way that Democratic voters were not for Obama in his two midterm elections."

Indeed, former President Barack Obama weighs in with the most negative mentions of the three presidents in the 2002-2018 midterm election years surveyed, largely from Republicans, at 16% for 2010 and nearly 27% in 2014 over the two-month period. And Obama got barely any positive mentions, at only 1% in both midterm election years.

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