[Yahoo] It's true that Obama remains generally popular in the state, but his approval rating has dipped to 49 percent, according to the most recent University of Wisconsin Badger poll -- a drop of 11 points since last winter. That's a higher approval rating than in other key battleground states this fall, but it's unclear at this point whether Obama's standing would hurt or help Feingold, who is virtually tied in the polls with his GOP opponent, businessman Ron Johnson.

Johnson has gained in the polls by trashing Feingold's votes on Obama-led agenda items like health care reform and last year's federal stimulus bill. And he has proved to be a serious financial challenger. In July and most of August, Johnson outraised Feingold, reporting $1.2 million in contributions, compared with the incumbent Dem's $900,000. Feingold had more cash in the bank earlier this summer -- but Johnson has readily dipped into his own cash reserves to bridge that gap, loaning his campaign more than $4.4 million, according to the Milwaukee Journal-Sentinel's Craig Gilbert.