(Reuters) – The fate of one of President Barack Obama’s key gun-control proposals appeared on Monday night to be in the hands of two senators: one Democrat, the other Republican, both of them longtime opponents of restrictions on guns.

Democratic Senator Joe Manchin of West Virginia and Republican Senator Pat Toomey of Pennsylvania are seeking a compromise on expanding background checks for prospective gun buyers. The proposal appears to be Obama’s best hope for meaningful gun-control legislation in the wake of the December massacre of 20 children and six adults at a school in Connecticut, where the president spoke Monday evening to a crowd that included some victims’ families.

If Manchin and Toomey can’t strike a deal, Obama’s calls to require nearly all gun buyers to submit to background checks for criminal records and mental health problems likely will fail, Senate aides said on Monday.

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