Tensions are mounting on Capitol Hill, and it’s not the usual bickering between Republicans and Democrats. 

On Thursday, the Senate for the third time rejected a House-passed bill to block President Obama’s executive order that protects nearly five million illegal immigrants from deportation as part of new spending authority for the Department of Homeland Security (DHS).

Related: DHS Funding Hits Obama’s Immigration Wall 

The vote was 52 to 47, or eight votes shy of the super majority needed to begin debate and eventually pass the legislation. The bill has gone down by a similar margin twice before.

The $40 billion DHS spending bill approved by the House directly challenges Obama, who angered Republicans with immigration orders circumventing their authority. Besides his move last November to limit the deportation of illegal immigrants, the president also blocked deporting some illegal immigrants brought here as children – the so-called “dreamers.”

Conservative House Republicans can’t fathom why Senate GOP Majority Leader Mitch McConnell (R-KY) isn’t delivering the 60 votes to pass the measure. Some Senate Republicans are also baffled by House lawmakers who aren’t grasping Senate realities.  

Rep. Michael Burgess (R-TX) told Politico this week that conservative voters are counting on the GOP majority in the Senate to deliver. “We sent them a bill and they need to pass it,” said Burgess, unwilling to acknowledge McConnell’s challenge. Sen. Bob Corker (R-TN) rolled his eyes and told reporters, “To pass a bill over here it takes 60 votes. Unless we can figure out some way of multiplying, it seems to me we have an issue that is very difficult to deal with.”

After their landslide November victory, gleeful GOP leaders saw an opportunity to push their agenda and pressure Obama. With 247 of 435 seats in the House and 54 of 100 seats in the Senate, Republicans hold their largest majority since 1929.

Related: GOP Could Give Obama’s Immigration Plan a Free Pass  

But while House Republicans can pretty much pass legislation at will, Senate Republicans are six votes short of the 60-vote super majority needed in most cases to achieve cloture and pass legislation. And with the Democrats largely united behind many Obama policies – especially on immigration reform – GOP leaders must woo at least a few Democrats on every major vote.

Senate Republicans enlisted Democratic support recently in passing a bill authorizing construction of the Keystone pipeline. They did it again earlier this week in unanimously passing a bill to provide suicide prevention programs to veterans. The immigration issue is another matter.

“These are expected, natural tensions that are going to happen with a new Republican Senate,” said political analyst Ron Bonjean, a former House GOP communications adviser. “They can try and show House Republicans they’re at their best, but there will be times when they’re not going to be able to attract Democrats to their measures.”

He added, “It’s a learning experience for many newer Republicans and some conservative members. It’s not necessarily going to be the Congress they dreamed of. There are going to be problems.”

Related: Voters Know What We Should Do on Immigration

Senate Minority Leader Harry Reid (D-NV), meanwhile, back at work after eye surgery, stood with McConnell on the Senate floor yesterday vowing to continue to block any DHS spending measure laden with obstructions to Obama’s immigration policies. Reid invoked recent terrorist attacks abroad in his warning. 

Congress late last year granted the DHS only a short-term extension on its funding, due to run out Feb. 27. Most employees essential to national security would keep working without pay, though DHS Secretary Jeh Johnson has warned of disruptions and risks.

“If you want to debate immigration, go ahead and debate immigration,” Reid told McConnell. “But not on the back of homeland security, leaving us totally naked and not giving us the ability to do what needs to be done to protect our homeland.”

McConnell voiced frustration that Democrats are denying the Senate a chance to vote on a bill that would keep DHS operating through next Sept. 30 – albeit with language to torpedo Obama’s immigration reforms. The president has vowed to veto such a bill, which would trigger a crisis and partially close the department.   

“There is a bipartisan desire to fund [DHS]. I’m sure we’ll resolve this sometime in the next few weeks,” McConnell said.

Related: Jeb Bush: Denying Dreamers Accelerated Citizenship Is ‘Ridiculous’ 

Ironically, for years as majority leader, Reid complained the GOP minority thwarted action on Democratic priorities and presidential nominations. Now, it’s McConnell complaining that Democrats are impeding key legislation.

The Republicans’ timing in threatening a DHS funding showdown couldn’t be worse. Many lawmakers are incensed and jittery about terrorist threats. Some Senate GOP leaders including John Thune of South Dakota and Corker, chair of the Foreign Relations Committee, have been signaling the GOP will have to cave and pass a “clean” appropriations bill with no controversial immigration language. 

House Speaker John Boehner (R-OH) sympathized with McConnell’s dilemma yesterday and said, “He’s got a tough job over there. I’ve got a tough job over here. God bless him, good luck.”

But he hinted House Republicans would be less than forgiving if the Senate folds and gives Obama what he wants. “The House fought this fight,” said Boehner. “We won. Now it’s time for Senate Democrats to work with Senate Republicans to stop the president.”

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