CHARLESTON, W.Va. -- Staffers for Sen. Joe Manchin, D-W.Va., and others would not comment Wednesday on a report that New York City Mayor Michael Bloomberg would have a fundraiser for Manchin later this month.The Buzzfeed website, which obtained an invitation for the event, reported the fundraiser earlier this week.Bloomberg, a political independent, founded Mayors Against Illegal Guns, a bipartisan group of more than 900 mayors. The group strongly backed expanded background checks on gun buyers in legislation introduced in April by Manchin and Sen. Pat Toomey, R-Pa. Bloomberg, a multimillionaire, spent millions of his own money backing the legislation.Manchin co-sponsored the background-check legislation in the wake of last December's shootings at Sandy Hook Elementary School in Newtown, Conn., that killed 20 students and six adults.The Manchin-Toomey amendment failed, but Manchin has said he would try again to expand the background checks.Manchin is a life member of the National Rifle Association, and has received the highest ratings from the National Rifle Association in the past. Nonetheless, he came under attack -- including in critical television ads -- from the organization after he co-sponsored the background check legislation. Manchin responded by running ads of his own, explaining his legislation and challenging the NRA.Jonathan Kott, Manchin's communications director, said he could not comment on Bloomberg's fundraiser because it is a political campaign event.No one responded to telephone calls seeking comments about Bloomberg's fundraiser from the West Virginia Democratic Party or from anyone working on Manchin's future political campaign. Manchin's Senate term runs through 2018.Contributions for admission to Bloomberg's fundraiser begin at $1,000, Buzzfeed reported.Last month, Buzzfeed reported, Bloomberg asked political donors to cut off their contributions to four Democratic senators -- Max Baucus of Montana, Mark Begich of Alaska, Heidi Heitkamp of North Dakota and Mark Pryor of Arkansas -- because they voted against the Manchin-Toomey amendment.Reach Paul J. Nyden at email@example.com or 304-348-5164.