Action Sports with Leigh Roche

The clock was ticking on the September deadline for immigration reform. The White House blamed Senate Democrats for insisting on acting quickly in the first place — and suddenly, the president was losing more Senate Democrats by the day.

Little had gone right since President Barack Obama announced in June that he would take unilateral action to fix the immigration system. But a flurry of calls for delay, delivered privately to the White House and publicly through the press in the last week, made it impossible for Obama to move forward, according to senior administration officials, congressional aides and immigration advocates.

Saturday morning’s announcement that executive action on immigration reform would be pushed until after Election Day was the end of a slow-motion unraveling that began with five words in June, when Obama pledged to act “before the end of summer.”

(Also on POLITICO: Obama disappoints, again)

Obama had barely exited the sun-soaked Rose Garden before White House aides, huddled under a small patch of shade, tried to downplay the rigidity of the deadline. But the damage was done, solidifying a timeline that Democrats feared more and more as Election Day neared.

Worried about alienating Hispanic voters, few Democrats publicly voiced their concern about making such a potentially controversial move as Democrats fought to retain control of the Senate. But the anxiety — confined, at first, to the most vulnerable Democratic incumbents — spread far beyond the key battleground states.

Public and private polling showed that unilateral action on immigration would harm Democrats locked in tight races in Arkansas, Louisiana, North Carolina and Alaska. If Democrats lost control of the Senate, immigration would be blamed for the defeat, the newly-installed Republican Congress would attempt to overturn the order and the rest of the Obama presidency would look even bleaker.

(Also on POLITICO: Obama's gamble: Will it work?)

Democrats also thought they risked doing long-term damage to immigration reform, similar to the way a controversial gun control law was blamed for 1994 Republican landslide or health care law contributed to the loss of the House in 2010 — forever polarizing the issue.

It was a stunning turnaround from two months ago.

When Obama strode into the Rose Garden in June, his shift to executive action didn’t seem crazy. Quite the contrary: It made sense to many Democrats.

Immigration reform fit snugly into the White House’s framing of the midterms as a choice between Democrats looking to get things done in people’s lives and Republicans refusing to do anything so they can score political points. With one executive order, Obama could defer deportations for potentially millions of undocumented immigrants and solidify his party’s advantage with Hispanics, one of the country’s fastest growing voter blocs.

(See POLITICO’s full immigration coverage)

He could motivate beleaguered Democrats and boost turnout among Latinos, labor and a wider progressive base that’s increasingly identified immigration reform as a top cause.

But the White House didn’t like the timeline. Senior administration officials privately blamed Sen. Dick Durbin (D-Ill.) and Sen. Chuck Schumer (D-N.Y.) for creating the expectation that Obama should take steps by the end of the summer. Facing pressure from activists in February, Durbin and Schumer were the first senior Senate Democrats to embrace the calls for executive action if the House failed to pass a bill by August.

Majority Leader Harry Reid (D-Nev.) also endorsed the demand for late-summer action, putting him at odds with Democrats fighting for their political survival in Republican-leaning states.

(Also on POLITICO: Obama says politics shifted on immigration)

So when Obama did the same, it looked like Democrats were finally unified.

“If Congress will not do their job, at least we can do ours,” Obama said, adding that he had asked Attorney General Eric Holder and Homeland Security Secretary Jeh Johnson for a slate of options. “I expect their recommendations before the end of summer and I intend to adopt those recommendations without further delay.”...