WASHINGTON — Sen. Pat Toomey's push on a new gun bill appears to have quickly fallen short.

The Pennsylvania Republican formally introduced a plan Thursday to bar suspected terrorists from buying firearms, but GOP leaders scheduled votes on four other gun bills, leaving his aside.

Republican leaders announced votes this coming Monday on competing GOP and Democratic proposals to expand background checks on gun buyers, and prevent gun purchases by people on federal terror watch lists.

None of the four are expected to pass, though. Instead, they reflect the longstanding partisan divides that have followed mass shootings like the one in Orlando. Each will provide election-year fodder, but little else.

The votes will come against the backdrop of the emotional response to Sunday's mass shooting and the heat of an election season that has Toomey in one of the nation's most pivotal races. His credentials on gun laws have been a key factor in his reelection bid, but have come under criticism from Democrats since the massacre.

Senate Democrats who want votes on background checks and the so-called "terror gap" made their point with a 15-hour filibuster that stretched from Wednesday into Thursday morning.

Toomey said he was trying to find a middle ground to close the loophole that allows suspected terrorists to buy guns.

"We're at a point here where this is really all about whether people want to get something done and they want to accomplish something that is going to make it more difficult for terrorists to obtain firearms, or whether they just want to make political points," he told reporters Thursday afternoon.

But hours later Republican leaders said they would vote on a different GOP plan to address that issue, choosing one put forward by Sen. John Cornyn (R., Texas). A Democratic version from Sen. Dianne Feinstein (D., Calif.) will also get a vote. Earlier versions of those two measures failed along almost strict party lines in December, shortly after the San Bernardino, Calif. shooting, when 60 were needed.

A background check bill co-sponsored by Toomey then also fell well short of passage.

Democrats said Toomey's plan to stop terror suspects from buying guns included "unworkable" hurdles that would tie law enforcement's hands. The campaign for Toomey's Democratic challenger, Katie McGinty, dismissed it as political posturing — and ultimately ineffective, given that GOP leaders chose a different option.

"Let's be clear, this bill is written to protect Pat Toomey's reelection campaign, not Pennsylvanians," said McGinty spokesman Sean Coit.

McGinty's camp had attacked Toomey for declining to support the Feinstein bill last year.

Democrats and Republicans have clashed over whether bills to bar terror suspects from buying guns give enough muscle to law enforcement to be effective, or enough recourse for innocent gun buyers whose purchases might be blocked by government mistakes or overreaching federal authorities.

Toomey said his plan represented a compromise, but it failed to attract support from either party and he could not seal a deal with the gun-control group founded by former New York Mayor Michael Bloomberg, Everytown for Gun Safety.

Toomey said Democrats and some Republicans have refused to budge off gun-law proposals that are sure to fail.

"Maybe there's some people who prefer that because maybe then there's a political issue," he said.

Responding to criticism that he's only warmed to the issue in an election year, a Toomey spokeswoman said his staff began talks with the Bloomberg group in March and received draft legislation April 4. His campaign also pointed to Vice President Biden's having praised, as recently as as Wednesday night, Toomey's work on background checks.

Toomey had criticized both the Democratic and Republican plans on the "terror gap" — though he voted for the GOP version in December.

He said the Democratic version did not give gun buyers enough opportunity to challenge a decision to block a sale, potentially stripping them of their Second Amendment rights without due process. He also said this week that the Republican version did not provide enough opportunity for authorities to stop a sale.

Those will be his two options when votes are taken Monday.

Toomey's plan would bar terror suspects from buying guns, but require the attorney general to go to court to permanently block such sales, putting the burden of proof on the government. A gun buyer could challenge the decision in court.

Under his bill, the attorney general could create a list of people barred from firearm buys — but the list would need review and approval by the Foreign Intelligence Service Court. For a new terror suspect not on the list, authorities would have three days to stop a gun sale and show probable cause to obtain a more permanent court order blocking it.

Democrats said creating a new terror list would be a lengthy, burdensome process and that if authorities had probable cause to suspect terrorism, the gun buyer would already be arrested.

Democrats argue that their version, from Feinstein, provides the attorney general power to move swiftly. It would let authorities to block sales when they have "reasonable belief" that the gun would be used in connection with terrorism. It would apply to people on federal terror watch lists as well as suspects not yet on such a list. They argue that such a provision could have helped stop a gun sale to the Orlando shooter, Omar Mateen.

The GOP alternative from Cornyn would give authorities three days to go to court to block a sale to a suspected terrorist — a time frame that Democrats said was impossibly brief to work, and easily evaded.

They dismissed Cornyn's plan as political cover.

jtamari@phillynews.com @JonathanTamari www.philly.com/capitolinq