Mack released a new televison ad Thursday outlining the difference between the two candidates' voting records. "Bill Nelson was the deciding vote for ObamaCare. I voted against ObamaCare," Mack says in the ad. "Bill Nelson voted to raise our taxes 150 times. I voted to cut taxes." Nelson released a hard-hitting spot last month that highlights some embarrassing moments from Mack's past, including bar fights and financial problems. The NBC News/Wall Street Journal/Marist poll was conducted Sept. 9 - 11. It surveyed 980 likely voters for a margin of error of plus-or-minus 3.1 percentage points.