WASHINGTON • Ohio Senator Rob Portman is facing a tough choice in the wake of the Orlando massacre: Stick with the National Rifle Association (NRA) or sign on to a compromise gun-control Bill the NRA hates.
Like several Senate Republicans in tight re-election contests in the United States, Mr Portman is weighing the cost of backing a proposal from fellow Republican Susan Collins to bar anyone on the govern- ment's no-fly list from buying firearms.
Whatever he and other vulnerable Senate Republicans decide on the Collins gun plan could determine their fates in the November election, with voters galvanised by the June 12 mass shooting that killed 49 people in an Orlando gay nightclub. The fallout may even factor into whether Republicans retain majority control of the Senate.
The issue is also roiling the House, where Republicans remained largely spectators as Democrats on Wednesday launched a lengthy, unprecedented sit-in on the floor of the chamber aimed at forcing votes on two gun-related measures.
Mr Portman, one of his party's most endangered lawmakers this cycle, is mostly quiet on his views on the compromise Bill.
"I need to look at it and see where she ends up," he told reporters on Tuesday, referring to Ms Collins.
Mr Portman, the best-funded of this year's crop of endangered Republican incumbents, faces headwinds in what polls have shown is a toss-up race in one of the nation's critical battlegrounds.
Keeping guns out of terrorists' hands is an issue that has overwhelming support among the public following the massacre in Orlando. Siding with the NRA against the Collins plan would risk ending what is likely to be the last chance for meaningful action by Congress this year on gun laws.
Mr Portman, who at times has flirted with a White House bid, needs the NRA's reliable, motivated supporters to turn out for him in November. On Monday he voted with his party for Republican proposals backed by the NRA but against a Democratic plan to bar people on the terrorism watch list from getting a gun. Afterwards, he put out a press statement saying he voted to keep terrorists from getting guns without mentioning his "no" votes.
The Republican plan, defeated in a procedural vote, would have required the government to get a court order within three days to block a gun sale. The plan was intended to provide due- process protections for people who are legally entitled to buy a firearm.
The Collins proposal would take the opposite approach, banning anyone on the no-fly list or another narrow list of possible terror suspects from buying guns, but giving people the right to appeal.
"I think the burden should be on the government," said Mr Portman, who touts his A rating from the NRA on his campaign website.
While the Orlando attack has revived efforts in Congress to advance gun restrictions, those proposals would need support from a significant number of Republicans to clear the 60-vote threshold in the Senate. So far, those measures have fallen short.
Democrats are determined to unseat Mr Portman as part of their quest for the majority this autumn. His Democratic challenger, former Ohio governor and congressman Ted Strickland, has been hammering him on the issue for days. The pair are currently tied at 42 per cent each in the Senate race, according to the latest Quinnipiac University poll released on Wednesday.
"I believe there can be no reasonable disagreement about commonsense gun safety measures like banning suspected terrorists from buying weapons, but Senator Portman disagrees - and in the process Portman has shown once again how out of touch he has become with the people of Ohio," Mr Strickland said in a statement after Monday's votes.