Rep. Carolyn McCarthy on Friday vowed to challenge Sen.-designate Kirsten Gillibrand in New York’s 2010 Democratic Senate primary, citing Gillibrand’s support from the National Rifle Association in past campaigns. McCarthy became active politically after her husband was killed when a gunman went on a shooting spree on a Long Island Railroad train in 1993, and has made gun control her signature issue since entering Congress in 1997. Her son was wounded in the shooting and still has health problems. “I certainly have never forgotten why I came into politics, so you can imagine how I felt when I heard that the next Senator from New York would be a person who got the endorsement of the NRA,” McCarthy said during an interview on MSNBC just minutes after Gillibrand was named to the Senate by New York Gov. David Paterson (D). McCarthy told the cable network that she had spoken to Paterson two weeks ago to air her objections to a possible Gillibrand appointment. “This is a personal issue to me,” McCarthy said. “It has nothing to do with politics. … I’m not out here to make trouble. … I had to speak up. I had to let the people know who their next Senator is going to be.” In a state dominated by liberal Democrats, Gillibrand has been unapologetic about her centrist views and has said that her pro-gun positions match those of voters in her upstate district. During the announcement of her appointment on Friday, she was careful to pay tribute to McCarthy and said she hoped they could work together on gun-safety legislation. Although some liberal groups are expressing skepticism about Gillibrand’s appointment, it remains to be seen whether McCarthy — or any other prominent Democrat — will be able to mount a credible primary challenge to Gillibrand next year. According to the New York Daily News, Manhattan Borough President Scott Stringer (D) is also contemplating a primary challenge to Gillibrand. And Jonathan Tasini, a labor activist who challenged then-Sen. Hillary Rodham Clinton (N.Y.) in the 2006 Democratic Senate primary, vowed that someone would run against Gillibrand from the left in the primary. “Make no mistake about it: The governor’s appointment is a caretaker,” Tasini said. “Rather than wring our hands, New Yorkers need to begin to organize today to elect a Democratic Senator in 2010 who will represent progressive values.” The Senator-to-be enjoys the enthusiastic support of New York senior Sen. Charles Schumer (D) and of new secretary of State Clinton, whose seat she will assume in the Senate. “Obviously, Chuck is looking at the politics of it,” McCarthy said. “That’s fine. I understand it.” Praise for Gillibrand came from other high places on Friday. President Barack Obama called Gillibrand “a wonderful choice,” and hailed her zeal for political reform. Senate Majority Leader Harry Reid (D-Nev.) said the Democratic caucus is eager to welcome their newest — and, at 42, youngest — colleague. “Gillibrand is a rising star in the Democratic Party who I am confident will quickly become a rising star here in the Senate,” Reid said.