Money is pouring into Alaska’s Senate contest, where polls are showing a surprisingly close race between Democratic-backed candidate Al Gross and incumbent Sen. Dan Sullivan (R).

Democrats have increasingly looked at the state as a potential pick-up opportunity with the prospects of a blue wave in the upper chamber growing more likely. And as the party’s optimism has grown, so has the amount of money spent on the race.

Outside groups supporting both Sullivan and Gross have funneled millions of dollars into the contest. The Lincoln Project, a prominent anti-Trump group, has spent more than $4 million there, while the Senate Leadership Fund, a GOP group, has poured $6 million into the race, according to the Center for Responsive Politics.

Polls still show Sullivan and President Trump leading in the state, but the gap has narrowed in the run up to Election Day. A recent New York Times-Siena College poll shows the president leading in the state by 6 points, while Sullivan leads by 8 points. By comparison, Trump won the state by nearly 15 points four years ago. Additionally, the nonpartisan Cook Political Report moved the race from “likely Republican” to “lean Republican” last week.

Still, strategists and consultants warn that Alaska is notoriously difficult to perform accurate polling in.

Democrats are seeking to appeal to the state’s many independent voters, who make up the largest voting bloc in the state, by backing Gross, an independent himself.

“Over the last few cycles in Alaska, as we’ve had independents run, there has been a documentable small but consistent bump that independent candidates seem to have enjoyed vis-a-vis the minority party,” said John-Henry Heckendorn, who worked as an Alaska political consultant before joining the private sector.

Sullivan and Gross joined incumbent GOP Rep. Don Young and his challenger Alyse Galvin in a virtual debate forum hosted by the Greater Fairbanks, Alaska Chamber of Commerce on Tuesday, to give one of their last pitches to voters one week out from  Election Day. 

Gross, an orthopedic surgeon and former commercial fisherman, has positioned himself as a moderate. He has voiced support for adding a public option for health insurance but is also a vocal supporter of conservative principles like Second Amendment rights.

“Al Gross has build a strong coalition of Alaskans who support him and want real change,” said Gross campaign spokeswoman Julia Savel. “Alaskans deserve better representation in Washington, DC and Al Gross is going to be the independent voice that brings that.” 

Former Sen. Mark Begich was the last Democratic senator to serve Alaska before Sullivan narrowly defeated him in 2014. Four years earlier, Begich defeated longtime Sen. Ted Stevens (R).

“[Alaska] has a long history of kicking out politician-y politicians, for lack of a better word,” said a source close to the Gross campaign. “It’s not a state that loves these entrenched-in-partisan-politics people representing them.”

Gross’s campaign has painted him as a maverick with a penchant for outdoor pastimes popular in Alaska such as fishing and hunting. A campaign ad released earlier this year touted Gross as being “born in the wake of an avalanche” and having “killed a grizzly bear in self-defense after it snuck up on him.”

“Dan Sullivan has voted with his party 97 percent of the time,” Gross says in the ad. “Out here, if you can’t think for yourself, you won’t survive.”

Gross’s backers say the ad plays well to Alaskans looking for a free-minded politician to represent them in Washington.

But veteran Alaska GOP strategist Art Hackney says the rhetoric has “been eye-rolled by most Alaskans.”

“Mostly it’s just the sheer weight of the amount of money that’s got everybody gagging up here,” Hackney said, referring to the outside money being spent on Gross’s behalf. “What a lot of people don’t understand is that there is a point of no return on money where it keeps getting spent. If you run the same ad 5,000 times rather than 500 times, its effectiveness is not only massively reduced, but it gets a lot more scrutiny from people. So, the things Gross built his campaign on have certainly come under a great deal of scrutiny.”

Sullivan previously served as the commissioner of the state’s Department of Natural Resources, as well as the attorney general. His campaign touts what they say is his strength on the economy, energy development, as well as military and national security issues.

“Our numbers look very positive,” Sullivan’s campaign manager, Matt Shuckerow said, referring to internal data.

He went on to dismiss left-leaning polls, including survey from Public Policy Polling showing a tight race.

“We see it every single year, every election cycle,” he said. “We see push polls issued by liberal organizations, the Democrat Party, and it’s all an effort to build traction, gain momentum, and to fundraise.”

Sullivan has taken a cue from national Republicans, painting Gross as an ultra-progressive pushing an “anti-Alaska agenda.”

In particular, Republicans have invoked audio reported by the conservative Washington Free Beacon in which Gross said he will caucus with the Democrats.

“That’s pretty powerful,” said Hackney of the audio.

Gross, however, would not be the first independent senator to caucus with the Democrats. Sens. Bernie Sanders (I-Vt.) and Angus King (I-Maine) both caucus with the party.

“He’s going to caucus with the Democrats because he feels that Republicans have failed on health care,” said the source close to Gross’s campaign. “But he also breaks with the Democrats a lot.”

Gross’s campaign has painted Sullivan as someone who religiously votes along party lines, hitting him particularly hard over the issue of health care. Alaska has some of the highest health care costs in the country.

The campaign has taken aim at Sullivan’s decision to vote to confirm Supreme Court Justice Amy Coney Barrett, citing the threat a conservative high court could pose to the Affordable Care Act. Sen. Lisa Murkowski (R-Ak.), a moderate Republican viewed as a swing vote in the Senate, also voted to confirm Barrett.

Sullivan has defended his decision, saying at a debate against Gross last week that he was proud to support Barrett.

The incumbent senator has also hit Gross over health care, arguing that Gross has made money off Alaskans as a health care provider and pointing as evidence to 2017 tapes where Gross is heard talking about his income as a doctor. The Sullivan campaign has dubbed them “the Gross tapes.”

“My opponent has no credibility on health care,” Sullivan said.

Gross has hit back, saying he was charging similar rates as other doctors and that the problem was the state’s expensive health care system.

Gross has said he stopped practicing full-time in 2013 and has since gotten involved in health care advocacy.

“When I get to the Senate, I will be the doctor that gets the public option across the finish line,” he said at the debate.

Gross has also hit Sullivan as out of touch, pointing to recent reports on Salon and The Intercept that allege ties between the senator and his family’s company, RPM International.

Shuckerow said in a statement last week that the articles do not prove there is a conflict of interest.

Regardless of who wins the contests, Alaska voters will likely not know the results of their elections the night of Nov. 3. The only results reported that night will be from in-person Election Day voting and in-person early voting through Oct. 29. Thousands of mail-in and absentee ballots won’t be counted until at least Nov. 10.