The Senate contest in Alaska remains unclear heading into Election Day, with new polls showing different results for the Republican, Democrat and write-in candidate who happens to be the incumbent Senator — and Democrats are paying for new ads in hopes that the intraparty battle will somehow boost their candidate.

A new Hays Research poll Thursday showed write-in candidate Sen. Lisa Murkowski (R) and Sitka Mayor Scott McAdams (D) rising in the unpredictable Alaska Senate contest and Republican nominee Joe Miller in third place, but a separate survey had a far different result.

A Hellenthal poll conducted for Murkowski backers showed the incumbent Senator leading at 45.7 percent, Miller at 30.4 percent and the Democratic nominee deep in third at 23.9 percent. The Hays poll put Murkowski at 34 percent, McAdams at 29 percent and Miller at 23 percent.

A longtime Alaska GOP operative described the Hellenthal poll as more accurate than the Hays poll, commissioned by a labor union supporting McAdams.

The Republican operative, based in Alaska but not affiliated with either Miller or Murkowski, argued that the Hays poll is not credible, never has been and should be ignored. The Republican said the Hellenthal survey might also be off-base but contended it is far more accurate than the Hays poll, adding that Miller would benefit from the state GOP’s strong get-out-the-vote machine and might still retake the lead from Murkowski.

“Miller’s people have well-greased turnout operation. Murkowski less so, but she has a lead,” this individual said Friday. It’s clearly possible that she could win this, but with some days left it’s very clear that Miller could win.”

Hays polled 500 likely voters Monday and Tuesday, asking respondents to choose from McAdams, Miller and “write-in candidate.” The survey has an error margin of 4.4 points. Hellenthal surveyed likely voters Monday through Wednesday, asking respondents to choose from McAdams, Miller and “Lisa Murkowski, as a write-in.” The poll had an error margin of 4.9 points.

Still, the Democratic Senatorial Campaign Committee is set to play in this race for the first time, going up with new ads for McAdams at the last minute. NBC’s First Read first reported the new ads.

The contest is competitive, and McAdams might be doing better than the Hellenthal poll suggests. The National Republican Senatorial Committee went on the air this week with an independent expenditure television spot attacking the Democrat. Miller has also gone up with an ad critical of McAdams.

Given that the DSCC is on the defensive in several races, the committee would likely not spend precious resources in Alaska unless it thought the money could help. Republicans are still expressing confidence in their ability to hold the Alaska seat, but they concede that Miller is in trouble. In fact, the Alaska GOP operative views the 30-second NRSC IE spot — which spends 25 seconds hammering McAdams and just 5 seconds praising Miller — as designed to boost either Miller or Murkowski.

“I certainly think must have been a lot of handwringing, because [the NRSC] came in and ran an ad that could only be described as wanting to make sure that either Miller or Murkowski won — because it didn’t do anything for Miller. I think they’re hedging their bets,” the Alaska GOP operative said.

Republicans don’t appear prepared to go as far as to say McAdams has a legitimate shot at pulling off an upset, although some on the GOP side disagree. But there is a growing consensus that Murkowski’s efforts at voter education about how to write her name in have succeeded to the point where it can be assumed that there will not be a significant drop-off in voters support for her at the polls versus the polling.

Either way, the result may be outstanding past election night, as Sen. Mark Begich (D) did not know he’d defeated Sen. Ted Stevens (R) for several days following the 2008 elections.

The Alaska GOP operative offered that the television ads attacking McAdams probably hit just in time to prevent him to rise past his two Republican opponents. A Washington, D.C.-based political operative who has been closely following the Alaska race agreed, although this individual conceded that Miller might not win, as once thought.

“As [Mississippi Gov.] Haley Barbour said: ‘Good gets better, bad gets worse.’ Figure out where Miller falls into that statement,” said a Washington, D.C.-based Republican operative who has been closely following the Alaska race. “I think he barely wins given the dynamics and the write-in. But Lisa can win.”