In their campaign ads back home, it’s as if the unpopular incumbent president doesn’t exist, as Republicans choose instead to highlight their own achievements or go on the attack against their Democratic challengers.

This deliberate approach underscores the difficult position Republicans find themselves in as they head into an election season that looks increasingly grim for the party. The senators don’t want to clash with Trump and rile up his stable of loyal supporters whose votes they will need to be reelected, but they also don’t want to hug him tightly him and turn off more moderate voters whose views of the president have turned negative.

“The sweet spot is finding real ways to show your independence and to do it in ways that don’t antagonize the base,” said Republican strategist Matt Gorman, vice president at the GOP consulting firm Targeted Victory…

In a closed-door party lunch last week, veteran GOP pollster Frank Luntz advised Republican senators to not disavow the president, but to put some daylight between themselves and Trump, according to two people familiar with his presentation who spoke on the condition of anonymity to describe the private remarks. Luntz also warned that this November’s congressional results could be similar to the 2006 midterms, when Democrats wrested control of both chambers away from the GOP after President George W. Bush’s popularity fell as a result of the Iraq War and Hurricane Katrina. Luntz did not respond to a request for comment.