Sen. Dean Heller’s (R-NV) seat has been at the top of every Democrat’s holiday wishlist for the past two years. But he’s not in a giving mood.

Heller remains very much in the fight against Rep. Jacky Rosen (D-NV) in their high-stakes campaign, Democrats’ best chance of defeating a GOP Senate incumbent and a must-win for the party as they seek to gain and not lose ground in the Senate.

National Democrats have been banking on a win in the state for months to have any hope at shrinking Republicans’ Senate majority. But Nevada continues to behave more like the perennial swing state it is than one being washed over by a huge Democratic wave. And the frenzied pace of early voting across the state indicates just how intense interest is on both sides of the aisle in the race.

Private polling of the race from both Democrats and Republicans shows Heller narrowly trailing Rosen in the contest, and Democrats privately feel more confident than the GOP that they’ll pull off a win. But the state is notoriously tough to poll, leading to a high level of anxiety for both sides in the campaign’s closing weeks.

And booming turnout across Nevada in the first four days of early voting voting suggests the race and a similarly tight gubernatorial campaign will far surpass the lackluster voter turnout of 2014 and even top the huge election boom triggered by then-Senate Majority Leader Harry Reid’s (D-NV) 2010 reelection fight.

“It’s about three-quarters of a presidential turnout. I’ve never seen that before — ever,” said Jon Ralston, Nevada’s top political reporter.

Turnout in Clark County, home of Las Vegas and more than two-thirds of the state’s population, has been bumping compared to previous midterm elections. Democrats are beginning to build up their firewall there with an intense focus on the city’s large Latino population and the suburban women who hate Trump, a must for any successful Democratic campaign. More Democrats have voted in Washoe County, the state’s traditional bellwether county and the home of Reno. That’s all good news for Democrats.

“We’re heading into Election Day with a very close race,” said Brandon Hall, a Nevada Democratic strategist who ran Reid’s 2010 race. “It looks to me like the Dems are off to a good start in the early vote, both in terms of the level of turnout and outpacing the Republican turnout.”

But ballots have been flooding in at near-presidential levels from the heavily conservative but lightly populated rural counties as well, a sign that Republicans are similarly hair-on-fire to vote this cycle. The results suggest that Reid’s vaunted Democratic turnout machine is still churning out votes at a rapid rate — but that Republicans may be catching up with their voter efforts after expending heavily to rebuild a once-broken state party.

“The ground game for Republicans is significant. They learned a lot from the amazing job Democrats did in the past,” said Sig Rogich, a GOP power player in the state and the former U.S. Ambassador to Iceland.

The intense interest in the race is especially notable given how pedestrian the two candidates are in most strategists’ eyes. The perennially cautious Heller has spent all election cycle carefully managing his relationship with President Trump, whose numbers are underwater in the state but who is beloved by the GOP base Heller needs to turn out in huge numbers.

Rosen, a first-term congresswoman, was deliberately chosen by party leaders to be the generic Democratic candidate after scandal-plagued Rep. Shelley Berkley (D-NV) cost them a winnable race against him in 2012.

“Heller has tried to do everything he can to lose the race, and Rosen hasn’t set the world on fire,” Ralston said. “She’s not very charismatic, she’s kind of boring, but she’s very disciplined and her campaign commercials have generally been good.”

That’s a read many local strategists concur with.

One local Democratic strategist referred to her as “smart” and “competent,” but said that she’d been deliberately selected as the party standard-bearer by Reid, who remains powerful in the state behind the scenes, because of her lack of political baggage.

“Democrats wanted this race. There were other bigger personalities out there and the powers that be decided that safe was the way to go here. From the very beginning the calculation was to play it safe and hope there’s a wave that pushes you over,” said the strategist.

One veteran Republican strategist in the state called Heller’s messaging “poor” and described his campaign efforts as lackluster, while worrying that Rosen hadn’t given him enough to attack her on.

“I just keep waiting for Dean to engage and really start fighting back, but he just hasn’t done that,” said the strategist. “And even if he were fighting he doesn’t have much to fight back against. Rosen probably doesn’t even know where the bathrooms in the capitol are yet.”

Heller has sought to make hay out of Rosen’s limited political experience, contrasting his lengthy record in Congress — especially his efforts to help veterans — with the zero bills she’s had signed into law.

He’s also worked hard to tie her to House Minority Leader Nancy Pelosi (D-CA) and California liberals, a traditional bogeyman in the state. And he’s featured popular outgoing Gov. Brian Sandoval (R) in ads to appeal to the state’s swing voters.

Rosen has responded by leaning hard into health care and preexisting condition protections, the message Democrats are campaigning on across the country, while charging Heller sold out the state’s voters after promising to protect their health care by voting to repeal Obamacare.

The race has drawn in huge amounts of cash, with outside groups fueled by billionaire Sheldon Adelson helping Heller keep pace on the airwaves in spite of Rosen’s superior fundraising. The Las Vegas media market has been deluged, and is currently the most expensive in the country.

The contest has also drawn in heavy hitters from both parties. President Barack Obama and former Vice President Joe Biden both stumped for Rosen and Democratic gubernatorial nominee Steve Sisolak in recent days. Sen. Bernie Sanders (I-VT) is on his way as well. And Heller had in President Donald Trump last weekend — a remarkable about-face given how critical he was of the president during the 2016 campaign.

The senator at one point said he was “99 percent against” Trump, and didn’t admit until months after the election that he’d voted for him. That triggered a primary challenge from perennial candidate Danny Tarkanian, and an implicit threat from Trump that the senator better get on board or get run over.

Heller got on board, backing Obamacare’s repeal after months of foot-dragging, and has spent the past year cozying up to the president. That helped convince Trump to get Tarkanian to switch to a House race instead, giving Heller a chance at survival.

As he rallied with Trump last weekend, Heller told Trump “everything you touch turns to gold.”

Democrats hope he’s wrong about Trump’s effect in the Silver State. But with the election already underway, few feel confident they know the answer.

“It’s more World War I, they’re both entrenched and moving incrementally, fighting over a small area in the middle,” said the Nevada Democrat. “It’s trench warfare.”