One week after the deadly mass-shooting at a gay nightclub in Orlando, Florida, the U.S. Senate is expected to vote on a series of proposals to block gun sales to terror suspects and expand screening of people buying firearms in the United States.

Despite universal condemnations of the attack and vows to find ways to prevent a repeat, is not clear that any gun control measure can pass Congress, where majority Republicans say Islamic State-inspired domestic terrorism is to blame for the shooting rampage that killed 49 people and wounded more than 50 others.

Democrats are undeterred, having commandeered the Senate floor for 15 hours late last week.

"We've done nothing.  Nothing at all," said Democrat Chris Murphy, whose Connecticut constituents bear scars from the 2012 mass-shooting at Sandy Hook Elementary School that left 20 children dead.  "I've had enough of the ongoing slaughter of innocents, and I've had enough of inaction in this body."

"Enough.  Enough.  Enough.  We cannot go on with business as usual," said Senator Cory Booker of New Jersey, one of more than three dozen Democrats who joined Murphy's floor action.

Democratic Sen. Cory Booker of New Jersey calls fo
FILE - Democratic Sen. Cory Booker of New Jersey calls for gun control legislation in the wake of the mass shooting in an Orlando LGBT nightclub earlier this week during a news conference on Capitol Hill in Washington, June 16, 2016.

Republicans insisted a focus on gun control is misguided.

"We need a strategy to defeat ISIS, which is the inspiration for these homegrown attacks here at home," said Senator John Cornyn of Texas.

But Republicans agreed to allow votes later Monday.  Murphy declared his efforts a success.

"We got a commitment from Republicans to bring two measures to the floor of the Senate for a vote: one that expands the number of background checks that are conducted, and the second that keeps terrorists off of the list of people who can buy guns," the Connecticut Democrat said.

Sen. John Cornyn, R-Texas, the Senate majority whi
FILE - Sen. John Cornyn, R-Texas, the Senate majority whip, arrives for hearing at the Senate Judiciary Committee on Capitol Hill in Washington, March 16, 2016.

Votes are also expected on Republican alternatives that spell out the rights of gun owners whose names might be added to the terror watchlist by mistake.

"We don't want terrorists to be able to walk into a gun store and buy a gun.  And we don't want an innocent, law-abiding citizen to be denied his Second Amendment rights because he is wrongly on a list with a bunch of terrorists," said Republican Senator Pat Toomey of Pennsylvania.  "This is not rocket science."

The Second Amendment to the U.S. Constitution states, "A well regulated militia being necessary to the security of a free State, the right of the People to keep and bear arms shall not be infringed."

The precise meaning of those words, and their application in modern America, have long divided the nation.

Political observers say Senate action on gun control is unlikely and House action even more so.

Supercommittee member, Sen. Patrick Toomey, R-Pa.,
FILE - Sen. Patrick Toomey, R-Pa., left, confers with an aide, on Capitol Hill.

"Is going after the Second Amendment how you stop terrorism?  No, that's not how you stop terrorism," said House Speaker Paul Ryan late last week.

Ryan's argument echoes that of America's biggest gun rights lobbing group, the National Rifle Association.

"This notion that more gun control is going to prevent some jihadist who thinks that he is going to obtain martyrdom by murdering innocent people really gets away from the serious nature of the problem we're facing," said the NRA's chief lobbyist, Chris Cox, on ABC's This Week program.

In a visit to Orlando last week, President Barack Obama pleaded for a bridging of political divides.

"I hugged grieving family members and parents.  And they asked, Why does this keep happening?'  And they pleaded we do more to stop the carnage.  They don't care about the politics," Obama said.

On one thing Democrats and Republicans agree, the Orlando attack won't be America's last mass-shooting.