WASHINGTON — Hillary Clinton’s once-huge lead over Bernie Sanders is eroding nationally and has vanished entirely in two early voting states, according to new polls Tuesday.

A New York Times/CBS poll showed the former secretary of state ahead of the Vermont senator by 48 percent to 41 percent nationally. In the same poll a month earlier, she was running away with the Democratic presidential primary with 52 percent to Sanders’ 32 percent.

The numbers in Iowa and New Hampshire were even more distressing for the supposed Democratic presidential front-runner.

A Quinnipiac University poll had Sanders leading by five percentage points in Iowa, 49 percent to 44 percent. That was a dramatic turnaround from December, when Clinton was clobbering her pesky rival 54 percent to 40 percent.

“Iowa may well become Sen. Bernie Sanders’ ‘Field of Dreams,’ ” said pollster Peter Brown of Quinnipiac University.

In New Hampshire, a new Monmouth University poll gave Sanders a 14-point lead among likely voters, 53 percent to 39 percent. Back in November, Clinton was ahead in the state 48 percent to 45 percent.

During a campaign stop in Iowa, Clinton went on the attack against Sanders’ gun-control record, evidence of Team Clinton’s concerns that her opponent was gaining ground.

“I find it kind of interesting, you know, he voted against the Brady Bill five times,” Clinton said. “He voted for what the NRA said was the biggest NRA priority, giving them immunity.”