WASHINGTON – Democrat Katie McGinty blasted Sen. Pat Toomey (R. Pa.) Monday for refusing to support a Democratic bill last year that would have banned anyone on a terror watch list from buying guns.

McGinty called on Toomey to now support the measure in the aftermath of the Orlando massacre, hours after Senate Democrats promised to bring the plan back up for debate.

"Pat Toomey has worked to allow suspected terrorists to buy guns in this country and that is just an outrageous position," McGinty, challenging Toomey in one of the country's most critical Senate races, said in a telephone interview. "Of all the kind of tough issues, this one should not be a tough call."

In response, Toomey's campaign criticized McGinty on a separate issue -- sanctuary cities -- and said Toomey "led the bipartisan fight to strengthen background checks on gun purchases," referring to a bill he sponsored after the 2012 Sandy Hook school shooting in Newtown, Conn.

McGinty's criticism Monday, however, referred to a politically-charged bill Senate Democrats proposed in December following a mass shooting in San Bernardino, Calif. Nearly every Senate Republican, including Toomey, voted against the measure. Toomey at the time said it "makes sense" to bar people on terror watch lists from buying guns, but that he was concerned that the bill from Sen. Dianne Feinstein (D., Calif.) might wrongly restrict people who are on federal watch lists due to an error.

Gun laws have become a political flashpoint for Toomey ever he co-sponsored the bill to expand background checks, winning national praise as the sole Republican to put his name on the proposal. He has used that effort as a symbol of his bipartisan work as he campaigns in a difficult re-election year, but Democrats have tried to undercut his credentials on the issue, questioning his commitment to the bill and challenging him to take tougher stands on guns.

"He leant his name to a bill, did little or nothing three years ago to try to get it passed, (and) since then has done absolutely nothing other than disavow any attempt to move on the legislation," McGinty said.

After voting against against the Democratic anti-terror gun bill in December Toomey supported a weaker GOP measure that would have also allowed the attorney general to stop suspected terrorists from buying guns – but only for 72 hours, unless the government could get a court order. Democrats derided that plan as toothless political cover.

McGinty on Monday said his vote against the Feinstein measure meant, "Pat Toomey has said he believes suspected terrorists should be allowed to buy guns in this country."

Pressed on whether Toomey supports the idea of terrorists obtaining guns, McGinty said the Democrats' renewed proposal "is his ideal opportunity to remove all doubt."

Democrats announced their plans to push for a vote on the bill Monday afternoon, saying it might have helped prevent the Orlando shooting because it would also allow the attorney general to block gun sales to people who are not on a watch list but still suspected of terrorism.

The FBI had twice interviewed the Orlando shooter over potential terror links, but had closed both cases.

Toomey earlier Monday reiterated his support for his background check proposal – but did not say how he would vote on the anti-terror plan.

"Sen. Toomey knows we could be doing more to keep guns out of the hands of people who shouldn't have them," spokeswoman E.R. Anderson wrote.

Toomey has long said he still supports the background check bill, and has been honored by the families of Newtown victims for his work on that measure. But Democrats point out that he has declined to reintroduce it and rarely talks about it.

He voted for it again in December after Democrats forced a vote on the bill.

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