(CNN) As chaos and confusion continued to swirl in Washington about the fate of some 2,000 migrant children separated from their parents at the border, a tweet from vulnerable Republican Rep. Mike Coffman on Thursday made it clear that Republicans are bracing for major blowback on the Trump administration's immigration policy in November.

Coffman, a Colorado US House member who is a top Democratic target this fall, took on President Donald Trump and his top policy adviser Stephen Miller, who helped shape the administration's "zero tolerance" policy toward illegal crossings at the border.

"The President should put a General, a respected retired CEO or some other senior leadership figure on the job of making sure each and every child is returned to their parents," Coffman tweeted. "And the President should fire Stephen Miller now. This is a human rights mess. It is on the President to clean it up and fire the people responsible for making it."

Coffman's tweet reflected the political gravity of the family separation crisis for Republicans as they try to maintain control of the House of Representatives in November.

As the President and his advisers have tried to blame Democrats for the heart-wrenching results of their zero-tolerance policy, many Americans -- including moderate Republicans and suburban women -- have recoiled in horror from the scenes and sounds of young children torn from their parents at the border.

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