The National Rifle Association is a “paper tiger” despite its much-vaunted reputation for political and lobbying clout, asserts a report released Tuesday by Sen. Christopher S. Murphy.

“This isn’t your father’s NRA,” the Connecticut Democrat said during a telephone press conference. “And the fact is, if the NRA was able to once put a scare into members of Congress, it shouldn’t any longer. It doesn’t win elections like it used to.”

Murphy released the report on the eve of a Senate gun violence hearing scheduled for Jan. 30, and as Congress considers proposed gun restrictions after the Dec. 14 mass shooting at Sandy Hook Elementary School in Newtown, Conn. It is the first in a series of reports that Murphy said will scrutinize the NRA.

Murphy said his goal is to debunk “the continuing mythology about the power of the NRA” and to convince his colleagues on both sides of the aisle that “there is nothing to fear” from the NRA. He pointed to a Sunlight Foundation analysis showing that the NRA’s PAC spent more than $11 million in the 2012 elections but enjoyed a less than 1 percent return on its investment. Sunlight determined that many of the races in which the NRA spent the most money did not go its way.

NRA officials did not return calls seeking comment, but in an advance copy of the testimony he will deliver to the Senate Judiciary Committee on Wednesday, NRA Executive Vice President and CEO Wayne LaPierre invoked the 4.5 million “moms and dads and sons and daughters” who the group counts as active members. About 250,000 of those members have signed up in the months since the Sandy Hook shooting.