Washington (CNN) While President Donald Trump doubles down on the incendiary immigration rhetoric that excited his base in 2016, the most vulnerable Republicans in 2018 find themselves under renewed attack from Democrats over the administration's "zero tolerance" policy at the border.

The battle is being waged in suburban House districts currently represented by Republicans, arguably the most important districts in the fight for control of the House. There, members of the President's party are facing pressure to distance themselves from the Trump administration's policy that has led to the separation of children from their parents at the southern border.

Particularly worrisome, Republican operatives say, is that the images and sound of children in detention facilities could have a lasting impact with suburban women and drown out the economic-success message the party has been pushing.

The responses from Republican members in these districts to Trump's policy have varied drastically. Some have broken with the administration completely. Others have criticized the policy but not the President or the administration, instead pointing blame at Washington inaction on immigration in general.

In her suburban district outside of DC, Virginia's Rep. Barbara Comstock released a three-paragraph statement in which she called for "a humane, bipartisan solution for all of these children and families," but made no direct mention of Trump, instead pointing to the "status quo" and the "broken immigration system" as causes for the family separations.

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