The Senate race in Maine between Susan Collins and Graham Platner started in a near tie, according to a New York Times/Portland Press Herald/Siena poll, but both campaigns may find reasons for anxiety in the survey.

Here are four warning signals for Mr. Platner, the Democratic nominee, and four for Ms. Collins, the Republican incumbent who is working to defend her blue-state seat in a difficult climate for her party.

Platner’s Problems

Voters don’t think he has good character.

Mr. Platner has for months contended with unflattering revelations about offensive posts he made online, a tattoo resembling a Nazi symbol he had covered up and his treatment of women. Those reports appear to have left an impression on voters: The survey found a majority of Maine voters did not judge Mr. Platner to have “good character” or the “right kind of moral values.”

Men without college degrees are not exactly flocking to him.

In Mr. Platner, a Carhartt-clad oysterman and college dropout, some Democrats saw a candidate who would resonate with blue-collar men. But many men without college degrees in Maine are not sold. Ms. Collins led Mr. Platner by nearly 30 points among white men without college degrees.

Voters think Collins will bring home more bacon.

Ms. Collins, chairwoman of the powerful Appropriations Committee, frequently promotes her work to support funding for projects in Maine, and the poll makes clear that her efforts resonate with voters. On the question of who would be better at bringing money and resources back to Maine, Ms. Collins held a 27-point advantage over Mr. Platner. Her advantage cut across geographic, racial, educational and gender divides.

He is seen as inexperienced.

Mr. Platner has appealed to voters by offering himself as an outsider without the baggage that many voters associate with career politicians. But the upside of having little political experience comes with a downside: Many voters say he lacks the background to be an effective senator.

Collins’s Problems

Platner does better with women.

Some of the most damaging reports about Mr. Platner’s past have concerned his attitudes toward women, but Democrats typically have an advantage at the polls with women, and the survey suggested Mr. Platner has retained much of that advantage. Overall, Mr. Platner led Ms. Collins among women, though more women said they would support a generic Democrat than said they would support Mr. Platner.

She is seen as too close to President Trump.

As Democrats work to turn the midterm elections into a referendum on the unpopular president, Ms. Collins has sought to create space between herself and Mr. Trump, breaking with him over the war with Iran and other issues. Still, most voters said she would be too supportive of Mr. Trump if re-elected, and voters said they thought Mr. Platner was more likely to be an independent voice.

Her age is a factor.

Ms. Collins would be 80 by the time she completed her next term, and that reality is apparently weighing on Mainers. Many said in the survey that she was too old to be an effective senator.

Voters have known Collins for 30 years, but they are not in love with her.

Perhaps no issue is more pressing than this for Ms. Collins: Three decades after Maine voters first sent her to Washington, most say they do not have a favorable view of her. The margin is narrow — 50 percent of voters said they viewed her unfavorably, and 48 percent said they viewed her favorably. But for a Republican candidate hoping to overcome major midterm headwinds in a Democratic-leaning state, Ms. Collins would surely like more voters to view her fondly.