The spike in donations reflects the prominence of President Obama's efforts to expand gun control measures, which have faced backlash from Republican lawmakers.
But the NRA is also going on offense on gun control, launching a four-state advertising blitz this week against three incumbent Democrats up for reelection in 2014 and one retiring Democratic senator.
Sens. Mark Pryor (Ark.), Mary Landrieu (La.) and Kay Hagan (N.C.), as well as retiring Sen. Jay Rockefeller (W.Va.), are targeted in the ads.
NRA brings in $1.1 million in January
The PAC now has $2.4 million cash on hand and no debt. It spent very little of that $1.1 million in January, contributing only $1,000 to Rep. Lynn Westmoreland (R-Ga.) and $2,500 to Rep. Bob Goodlatte (R-Va.).