A fight in the Senate that could result in shutting down the Department of Homeland Security this weekend really comes down to one thing: a fight over immigration. Now the question is which side will blink first.

In January, House Republicans passed a bill that linked continued funding for DHS with a repeal of President Obama's executive actions on immigration. Despite easy passage in the House, it has stalled in the Senate.

On Monday, the bill received 47 votes for and 46 against, falling short of the 60 votes needed to bypass a Democratic filibuster. Funding for DHS runs out on Friday; without passage of a new funding bill, the department would shut down.

“Right now, that does seem to be where we’re headed,” said White House press secretary Josh Earnest during Monday's press briefing.

The White House is hoping to use fear of a possible shutdown to convince Republicans to de-couple the funding for DHS and the repeal of Obama's amnesty moves.

But even if DHS does shut down that doesn't mean lawlessness on the streets. Front line security officers would stay on the job while backend office workers would be sent home until the funding issue is settled.

The New York Times is citing renewed threats, such as the al Shabab video promising an attack on the Mall of America, as one reason GOP lawmakers in the Senate may back down.

The Washington Post reports that Senate Majority Leader Mitch McConnell is looking to set up separate votes later this week on immigration and DHS funding.

“It’s another way to get the Senate unstuck,” McConnell said.

Meanwhile, House Speaker John Boehner is calling on the Senate to pass the bill as is, putting blame squarely on Senate Democrats for blocking the bill through procedural motions.