GREEN BAY, WI (WTAQ) - A new poll shows that the race for Wisconsin’s open U.S. Senate seat is closer than ever.

Rasmussen Reports surveyed 500 likely voters by phone last Thursday – and 48 percent favored Republican Tommy Thompson to 47 percent for Democrat Tammy Baldwin.

The survey was taken before their final debate last Friday night.

The contest is technically a dead heat, since the one percent difference is well within the poll’s error margin of 4.5 percent.