Gov. Janet Mills is not dropping out of the U.S. Senate race despite trailing in the polls and having no advertisements booked after Wednesday, her campaign spokesperson said.

Speculation online about the potential for Mills to drop out, fueled primarily by supporters of her competitor, Graham Platner, mounted this week as ad spending data compiled by AdImpact showed Mills having no ads booked in the coming days.

“As the only Democrat elected statewide in Maine in the past 20 years, Janet Mills knows how to win tough battles and deliver results — and that’s why she’s the best candidate to beat Susan Collins in November and is running full steam ahead to defeat her,” Tommy Garcia said in a written statement.

After Wednesday, her campaign has booked no TV, satellite, radio or digital ads, AdImpact showed — an unusual move for a major candidate. Platner, by contrast, has some $190,000 in ads planned through next week.

Garcia declined to discuss internal campaign strategy, including whether a new flight of ads is imminent. But he continued to make the case that Mills is the best candidate to take on Republican Sen. Susan Collins in the fall.

“Republicans are foaming at the mouth to run against Graham Platner and are prepared to put hundreds of millions of dollars behind ads on his never-ending controversies,” he said. “This campaign will continue making this case to voters.”

Platner, who is leading in the polls and has raised about three times as much money as Mills, has turned his attention to Collins in recent days.

There are numerous signs Mills is in the race to stay.

This week, her campaign announced that it raised $2.6 million in the first quarter and released a detailed policy platform. And she was the first candidate to publicly confirm her participation in three televised debates and two other forums hosted by the Maine Democratic Party.

Advertising is arguably more important for Platner, a political newcomer, than it is for Mills, who has spent her life in public service and is widely known.

The 41-year-old oyster farmer and combat veteran was a virtual unknown before bursting onto the scene last August and securing an early endorsement from prominent progressive Sen. Bernie Sanders of Vermont.

Meanwhile, Mills, a former attorney general, is finishing her second term as governor, a position that keeps her in the public eye.

The lack of advertising, which was first noted in the Bangor Daily News, comes after Mills launched a series of attack ads against Platner. The spots highlighted some of his controversial online comments about sexual assault and the skull-and-cross bones tattoo resembling a Nazi image that he had covered.

On Wednesday, Mills had a few hundred dollars worth of buys booked in support of an ad featuring a U.S. Army veteran and rape victim slamming Platner for online posts he made in 2013 blaming victims of sexual assault. But she’d committed no money beyond then as of Wednesday afternoon.

Platner has apologized for the comments, saying they don’t reflect who he is today.

“Maine, I am asking you not to judge me for the worst thing I said on the internet on my worst day 14 years ago, but who I am today,” Platner said in an ad that’s no longer running.