U.S. Rep. John Katko holds a 14 percentage-point lead over Dana Balter heading into the final days of their campaign for Congress, according to a new poll made public Sunday.

Katko, R-Camillus, leads Balter, a Syracuse Democrat, 53-39 percent among likely voters, according to the Syracuse.com/Spectrum News/Siena College poll. About 8 percent of voters are undecided ahead of the Nov. 6 election.

The poll showed that despite almost $8 million in spending by both sides to win votes, there's been no significant change among voters since late August. The same poll showed Katko leading 54-39 percent two months ago in the 24th Congressional District.

The new poll of 500 likely voters was conducted by live operators who called land lines and cell phones Oct. 18-22. The poll has a margin of error of plus or minus 4.6 percentage points.

One reason Balter failed to gain ground, the poll found, is that voters now have an unfavorable view of her -- one that increased as people became more familiar with the first-time candidate.

In August, voters had a favorable view of Balter (32-23 percent) but about 45 percent of voters said they didn't know enough about her to have an opinion.

In the new poll, voters had an unfavorable view of Balter (33 percent favorable, 42 percent unfavorable) and 25 percent said they didn't have an opinion.

"There is no question that the campaign has taken a toll on her," said Steve Greenberg, a spokesman for the Siena College Research Institute. "Her unfavorable rating over the past eight weeks has gone up 19 points. Clearly, the campaign has had an effect on the way the electorate views Balter."

Katko and independent groups that support him have paid for negative ads over the past two months that portrayed Balter as radical and extreme in her political views. The ads also portrayed Balter, who teaches at Syracuse University, as an outsider who is not familiar with Central New York or the issues that people care about.

As of Oct. 17, Katko had spent more money the campaign than Balter, $2.3 million to $1.74 million, according to Federal Election Commission records.

Independent political groups have spent nearly $4 million on the election, almost evenly split between the two candidates, as of Friday.

Katko continues to run strong in a year when Republicans in swing districts like the 24th were viewed as endangered nationwide, part of a predicted blue wave that could turn the House over to the Democrats. Katko is one of only 25 Republicans to represent a district Hillary Clinton won in 2016.

The poll found Katko held his lead by receiving support from outside his own party. The second-term Republican has emphasized his bipartisan work.

Independent voters who are not enrolled in a political party favor Katko (53 percent) over Balter (40 percent), according to the poll. Katko also has more crossover support among Democrats (20 percent) than Balter does among Republicans (10 percent).

Greenberg, the Siena pollster, said Balter could still make up ground in a district where enrolled Democrats (34 percent) outnumber Republicans (33 percent) by about 5,000 voters. About 25 percent of the district voters are not enrolled in a political party.

"It seems to me the Balter campaign has to do three things - win back Democrats, find a way to win independent voters, and find a way to turn out Democrats in a way they don't turn out historically in midterm elections," Greenberg said.

Despite the enrollment advantage for Democrats in the district, more Republicans voted (41 percent) than Democrats (37 percent) in the last midterm election four years ago.

Katko won that 2014 race by about 20 percentage points over former Democratic Rep. Dan Maffei. Katko won by the same margin in 2016 over Democrat Colleen Deacon.

Central New York voters told pollsters in the past week that they would prefer to see Republicans keep control of Congress, 49-44 percent. But voters are split on their approval of the job done by President Donald Trump (48-48 percent).

Katko, who did not endorse or vote for Trump, has walked a fine line with Trump supporters. He has criticized the president on some issues, but also welcomed Vice President Mike Pence and Trump daughter, Ivanka, to Syracuse for joint appearances with him.

Katko and Balter have disagreed over the impact of federal tax cuts that took effect in January. Katko says the cuts have helped local companies and their employees. Balter says the cuts have disproportionately helped corporations and wealthy individuals.

When the poll asked voters if their financial position had changed in the past two years as a result of the federal government's work, 48 percent said they had seen no change. An additional 31 percent said their financial situation had improved, and 19 percent said it had worsened.

The poll found Balter continues to draw her base of support from the city of Syracuse, where she leads by 64-26 percent.

Katko leads in the Onondaga County suburbs by 15 percentage points (53-38 percent) and in Cayuga, Oswego and Wayne counties by 17 points (50-33 percent).

The 24th Congressional District covers all of Onondaga, Cayuga and Wayne counties, and the western half of Oswego County, including the cities of Fulton and Oswego.

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