A new poll from Fox News shows U.S. Rep. Marsha Blackburn with a narrow edge over former Democratic Gov. Phil Bredesen in Tennessee's U.S. Senate race.

The poll, released Wednesday, found 47 percent of likely voters surveyed said they'd vote for Blackburn, compared to 44 percent for Bredesen.

Eight percent were undecided.

Blackburn's edge in the Fox News poll fell within the survey's margin of error of plus or minus 3.5 percentage points.

But the poll found that Bredesen had an edge over Blackburn in terms of favorable views voters have of him compared to unfavorable.

Tennessee U.S. Senate race polls:Phil Bredesen, Marsha Blackburn vie to replace Bob Corker

Fifty-four percent of likely voters had a favorable view of Bredesen while 51 percent had a positive view of Blackburn.

At the same time, 36 percent of respondents had a negative view of Bredesen while 39 percent held an unfavorable view of Blackburn.

In terms of where the candidates are getting their support, among likely voters identified as moderates, 58 percent said they would vote for Bredesen, compared to 24 percent for Blackburn.

Bredesen netted support from 10 percent of likely Republican voters while 83 percent said they'd vote for Blackburn. By comparison, 93 percent of Democrats said they would vote for Bredesen, compared to just one percent who said they would cast a ballot for Blackburn.

On the issues, 29 percent of likely voters said the economy is the most important issue in the race. Twenty-seven percent of respondents said health care was the top issue.

Overall, the poll of likely voters consisted of 53 percent Republicans, 35 percent Democrats and 12 percent independents.

Fox's poll, conducted under the joint direction of Anderson Robbins Research and Shaw and Company Research, was done using landline and cellphones. A total of 686 likely voters were surveyed over a four-day period beginning Sept. 8.

The Fox poll is the latest in a series of surveys that have shown the race between Bredesen and Blackburn to be tight.

A NBC News/Marist poll released last week showed Bredesen with a 2 percentage-point edge over Blackburn. That lead also was within the poll's margin of error.

NBC News/Marist poll:Phil Bredesen holds slight edge over Marsha Blackburn

Reach Joel Ebert at jebert@tennessean.com or 615-772-1681 and on Twitter @joelebert29.