Washington (CNN) Just five months before the midterm elections, Republicans are scrambling to distance themselves from the Trump administration's widely panned "zero tolerance" immigration policy that has resulted in the separation of children from their families at the southern border.

As images of children being held in cages at detention centers near the border flash across television screens, Republicans are being pressured to take a stand on Trump's controversial policy, as the President and the administration continue to place blame on Congress for inaction on immigration legislation.

One of the strongest statements criticizing the administration came late Monday from Rep. Steve Stivers, who chairs the National Republican Congressional Committee, the House GOP's campaign arm. In a sign of just how damaging Republicans believe this issue can be in the fall, Stivers said he was writing a letter "to understand the current policies and to ask the Administration to stop needlessly separating children from their parents."

"If the policy is not changed, I will support other means to stop unnecessary separation of children from their parents," he added.

The statement is a clear signal to vulnerable Republicans worried about keeping their seats in November that they can break with Trump on this issue.

One senior Republican operative, who spoke to CNN on condition of anonymity to speak candidly about a hot-button topic, said the story was "hitting home."

"Worst of all, it's not just affecting border districts but suburban women as well," the operative added.

The Trump administration is facing wave of criticism from popular GOP figures over its separation of families. Former first lady Laura Bush wrote that the family separation policy is "cruel. It is immoral. And it breaks my heart." Massachusetts Gov. Charlie Baker, the nation's most popular governor, revoked his offer to send National Guard help to the southern border because "the federal government's current actions are resulting in the inhumane treatment of children."

Trump's former White House communications director Anthony Scaramucci called it "an atrocious policy" on CNN Monday. "It's inhumane. It's offensive to the average American," he said.

Democrats have gone all-in to draw attention to the family separations. A Democratic delegation visited an immigrant detention center on Sunday, which was Father's Day, to highlight the issue. And California Sen. Kamala Harris called on Homeland Security secretary Kirstjen Nielsen to resign Monday.

A new CNN poll out Monday found that 67% of Americans oppose the separation of children from their parents, with 68% of independent voters disapproving of Trump's position. Among Republicans, however, 58% approve of the policy.

Colorado Rep. Mike Coffman, one of the nation's most endangered Republicans in this year's midterms, said in a statement he told Sen. Dianne Feinstein on Monday he wanted to "help her put a stop to this human rights disaster at the border" and was willing to introduce the California Democrat's bill to do so in the House.

"This isn't who we are," Coffman said. "My colleagues should mark their words and this moment -- history won't remember well those who support the continuation of this policy."

Still, for some Republicans, breaking with Trump has the potential to be politically perilous and many in Congress are trying to avoid it.

Some are blaming Attorney General Jeff Sessions. Others are lambasting a do-nothing Congress. And a few are dodging the questions entirely.

"Jeff Sessions could change this today," Texas Rep. Will Hurd, one of the most outspoken Republican critics of the Trump administration's policy, said on CNN Monday.

"Neither party should want to separate kids from their parents," California Rep. Jeff Denham, another endangered Republican, said on CNN hours later.

Their responses underscore the challenge facing the GOP in November's midterm elections: The party's base is still loyal to Trump and animated by the hardline anti-immigration platform he ran on. But the images of children separated from their parents and kept in cages near the border -- beyond humanitarian concerns -- are the makings of a political disaster just five months from election day.

Already, several Republicans have faced primary voters' wrath for breaking with Trump. South Carolina Rep. Mark Sanford was ousted in a primary last week. Alabama Rep. Martha Roby faces a runoff. And Arizona Sen. Jeff Flake decided to resign, saying he couldn't win a primary while standing for his principles and criticizing Trump.

Two years after immigration was the central theme of Trump's successful presidential campaign, the issue threatens to damage his party's chances now that the businessman-turned-politician is President.

Missouri Attorney General Josh Hawley, who is challenging Democratic Sen. Claire McCaskill, picked up on Trump's talking point and blamed Democrats -- without addressing the reality that the family separations are the result of a Trump administration policy and without taking a position on the policy.

"The whole immigration system is a disaster, and Claire McCaskill should answer for that: she's been in D.C. for over a decade and she has shown zero leadership to secure the border, stop sanctuary cities, or protect American workers," Hawley said in a statement. "Nobody wants to see children and parents separated, just like no one should want to see illegal drugs and gangs pouring across our border. But none of that will change until McCaskill and the D.C. crowd take some responsibility and build the wall and secure the border."

Some Republicans in competitive races this fall broke with Trump on the policy but didn't directly blame the President, instead choosing to vaguely blame Washington or Congress.

"I do not favor separating families. Washington is to blame for this by being all talk and no action, and the solution is to secure the border," Florida Gov. Rick Scott, who is challenging Democratic Sen. Bill Nelson, said in a statement.

Megan Taylor, a spokeswoman for Nevada Republican Sen. Dean Heller, said: "Senator Heller doesn't support separating children from their families, and he believes that this issue highlights just how broken our immigration system is and why Congress must act to fix it."

Denham's district in the Central Valley of California is a Democratic target in November. His opponent, Josh Harder, called him "Do-Nothing Denham" in a statement Monday.

"I have no doubt Trump and Denham's lack of leadership on immigration spell deuces for Republicans in the midterm elections, especially in a district like ours, with over 40% registered Latino voters," Harder said.