A Libertarian-minded policy group has called on U.S. Sen. Pat Toomey to pledge that he won't cast any votes to fund Obamacare.
The Lehigh Valley Republican has been a regular critic of President Barack Obama's historic health care reform, however a spokeswoman would not be drawn on whether Toomey would take such a pledge.
"Since the law's adoption, Sen. Toomey has been clear -- it must be repealed," said Toomey spokeswoman E.R. Anderson via email. "He has voted to defund or repeal the President's health care law at every turn."
The group pressuring him, the Republican Liberty Caucus of Pennsylvania, announced Thursday that it passed a resolution calling for Toomey to sign a petition letter authored by Sen. Mike Lee, R-Utah.
Lee's letter promises not to vote for any continuing funding resolutions or appropriations that enable further implementation or enforcement of the president's Affordable Care Act.
His involvement may complicate matters for Toomey.
As chairman of the Senate Steering Committee, a caucus of conservative senators that includes the majority of the Republican conference, Toomey tapped Lee to serve as his co-chairman earlier this year.
Regardless of the Lee letter, Anderson said the junior senator's position on Obamacare and voting record are unmistakable.
"He is an original cosponsor of the Obamacare Repeal Act and the Defund Obamacare Act introduced by [Republican Texas] Sen.Ted Cruz," she added. "As the American people become increasingly aware of how awful this law is for them, the Senator is hopeful that momentum will continue to build to overturn it."