Rasmussen continues to show a tight Senate race in Wisconsin:

Democratic incumbent Russ Feingold and his chief Republican challenger Ron Johnson remain locked in a neck-and-neck battle for the U.S. Senate in Wisconsin. The latest Rasmussen Reports telephone survey of Likely Voters in Wisconsin finds Johnson with 47% support, while the Democrat earns 46% of the vote. Two percent (2%) like some other candidate in the race, and six percent (6%) are undecided. This is the third straight month with Feingold attracting 46% of the vote and all three months have shown a close race. A month ago, Johnson had 45%. Two months ago, Johnson was at 44%.

Johnson has already been up on air with TV and radio ads--you can watch them here--and has indicated he's willing to spend more than $10 million of his own money to bankroll his campaign through the fall. Russ Feingold has dismissed Rasmussen's polling, but the Democratic firm Public Policy Polling is showing a very tight Wisconsin Senate race as well.

George Will profiled Johnson, an Ayn Rand-loving pro-life Lutheran businessman from Oshkosh, in May.