Republicans happily pointed out an ominous parallel in Democratic polling of Wisconsin Senate races Tuesday.

The Democratic-leaning Public Policy Polling released a survey showing Sen. Herb Kohl (D-Wis.) in a "pretty solid position" with a 50 percent approval rating.

Moreover, the Dec. 10-12 survey shows him with leads over potential GOP rivals Rep. Paul Ryan, former Gov. Tommy Thompson and state Attorney General J.B. Van Hollen ranging from 6 to 13 points.

And if Kohl decides not to run for reelection in 2012, as some have speculated, and Russ Feingold opts to make a bid, the defeated senator has a good chance of getting his job back. Feingold, who lost in 2010, polls similarly to Kohl in the same match-ups with the Republicans, and leads Ryan by 7 points, according to PPP.

"Wisconsin Senate looks good for Dems," the North Carolina-based firm concludes. 

But PPP made a similar proclamation in November 2009, the National Republican Senatorial Committee pointed out.

"Feingold looks solid," PPP said then.

Feingold lost to Republican Ron Johnson by 5 percent. (PPP's last survey before the vote gave Johnson a 9-point lead with 3 percent undecided.) The November 2009 PPP survey, however, didn't include Johnson, who declared in May of 2010.