When Sen. John Sununu (R-N.H.) was down 20 points in the polls earlier this year, Democrats and even some Republicans wrote off his re-election campaign.

Even National Republican Senatorial Committee Chairman John Ensign (Nev.) said he had his doubts.

“John Sununu told me six months ago, he laid out what was going to happen in this race, and it is happening exactly like he said it would,” Ensign said last week. “I was skeptical when he said that, but it’s happening exactly like he said it would.”

At a joint event last week with Democratic Senatorial Campaign Committee Chairman Charles Schumer (N.Y.), Ensign revealed that NRSC tracking polls showed Sununu within 4 points of former Gov. Jeanne Shaheen (D) — a far cry from the state of the race earlier this year.

“Our own polling had him 14 points down [earlier this year],” Ensign said. “And he has literally closed in the last several weeks, then he stayed about 9 points down for a while, then he stayed about 6 points down for a week and half, and now it’s about 4 points.”

The NRSC would not disclose details of its tracking polls.

Public polls show Sununu trailing Shaheen by more than 4 points. A poll taken for the Concord Monitor gave Shaheen a larger lead, 50 percent to 43 percent, among 600 likely voters interviewed on Oct. 17-19. The Research 2000 poll had a 4-point margin of error.

“The polling we’ve seen is much more in line with the Concord Monitor poll than the numbers the NRSC seems to have,” said DSCC spokesman Matt Miller, who declined to give out his committee’s survey of the race.

Republicans say Sununu was behind until Election Day in 2002, when he upset Shaheen with a 51 percent to 47 percent victory. Miller disputed that, saying polling showed Sununu was only trailing his opponent in the primary, plus the Senator should be ahead this cycle because he is running as an incumbent.

But Sununu might have bigger problems on his hands than polling history.

GOP presidential nominee Sen. John McCain (Ariz.) was expected to have a good shot at winning New Hampshire, but he is quickly falling behind Democratic nominee Sen. Barack Obama (Ill.).

Sununu must also play well in the GOP-leaning 1st district, where former Rep. Jeb Bradley (R) is challenging Rep. Carol Shea-Porter (D), who won the seat in 2006 in an upset. While Bradley initially led Shea-Porter in polling through September, the Democrat now generally boasts a single-digit lead over the Republican in the same polls.

Rockingham County Democratic Chairwoman Lenore Patton said she sees Sununu as the strongest candidate on the GOP ticket but predicted he has about the same chances of winning as Bradley on Election Day.

“I would say that probably he’s got fewer negatives than Bradley and McCain, so he might be a little stronger than them,” Patton said. “But I don’t think he’s going to be strong enough to win.”

Patton said that while this Senate race is now competitive, it seems Sununu’s campaign has been static these past few weeks.

“The perception is that he’s been stagnant,” she said. “With a week to go, if he hasn’t moved up in the polls, he’s not going to.”

Many New Hampshire Democratic insiders are confident that Shaheen is going to win, though their Republican counterparts still consider the Senate race to be a tossup. What’s more, some Republican insiders see Bradley in a better spot than Sununu.

A least one high-level Granite State Republican said he could envision an Election Day scenario in which Sununu comes up short by a few points in his race, but Bradley ekes out a win in the 1st district. The same high-level Republican said he could not envision an Election Day scenario in the reverse.

But Granite State Republican strategist Greg Moore said that while McCain and Bradley slip behind, Sununu at least appears to be on the upswing.

“If can he continue to close the gap between now and Election Day, he can certainly pull this off,” Moore said.

Moore said the question remains whether Sununu can successfully run ahead of other Republican candidates in the state to keep his seat.

Still, Sununu’s relative comeback puts him in a better spot than some of his fellow New Hampshire GOP candidates — and almost every other Republican Senator in the country up for re-election this cycle.