Strange to think that Republicans are pinning their hopes on Senator Kennedy. It is, however, Mark, not Ted, who is the object of GOP affection.

Several weeks ago, I profiled the most endangered Senate Republican, Rick Santorum of Pennsylvania. This week it is Rep. Mark Kennedy of Minnesota, the Republicans’ best chance to pick up a Senate seat.

Minnesota has not traditionally been a bastion of Republican strength, but the GOP is increasingly competitive there. George W. Bush ran well there in 2000 and 2004, losing by only 2.6 and 3.4 percent, respectively. In 2002, Minnesota elected Republicans Tim Pawlenty and Norm Coleman to the governor’s office and the Senate. Its House delegation is split 4-4.

While the state still has a bit of a Democratic lean, its political parties are perhaps the most polarized in the country. In the 1990s, the state was represented by the late Paul Wellstone (D), whom National Journal rated as the most liberal senator for seven of his 12 years, and Rod Grams (R), who was regularly rated as one of the 20 most conservative senators. The polarization of the parties opened room in the middle for the third-party victory of Jesse Ventura, but Ventura and his followers have faded from the scene, and there is no third-party challenge in the Senate race.

Out of this political climate comes Mark Kennedy, who was elected in 2000 and represents the 6th District, which encompasses the suburbs north and west of Minneapolis and St. Paul. He was the Republicans’ first choice to run for the Senate, and they cleared the primary field for him. Kennedy is more conservative than the moderate Republicans David Durenberger and Rudy Boschwitz who represented Minnesota in the Senate in the ’80s, but he is somewhat less conservative and more politically attuned than one-term-wonder Grams.

Kennedy had an edge over Dayton and was favored over other Democrats enmeshed in a messy primary, but Democrats have improved their fortunes.

First, a millstone was lifted from their necks when Dayton recognized his poor job approval ratings and decided not to seek reelection. Second, the party has recently unified around Amy Klobuchar. She had been opposed by child-safety advocate Patty Wetterling, who had run for Congress against Kennedy in 2004.

Wetterling pulled out of the race last month. Potential self-funding candidate Mike Ciresi also bowed out. Klobuchar is still formally opposed by Ford Bell but is expected to win the nomination handily.

Klobuchar is the county attorney for Hennepin County, which contains one-quarter of the state’s population. She is a traditional liberal on many matters, but her law-and-order credentials moderate her politics in some areas. With Democrats united behind Klobuchar and low national numbers for Republicans, she has developed a small lead over Kennedy in several recent polls. But essentially this race is now a tossup, and in a dreary year for Republicans Kennedy’s even chances look good compared to their other prospects.

With Santorum in deep trouble and the group of Conrad Burns (Mont.), Lincoln Chafee (R.I.), Mike DeWine (Ohio) and Jim Talent (Mo.) braced for competitive races, Republicans were dismayed to see Democratic Rep. Harold Ford running even or ahead of Republican rivals in the Tennessee seat being vacated by Senate Majority Leader Bill Frist (R). Republicans are unlikely to lose all six of those seats, but if a strong wind blows in the Democratic direction the Minnesota race will be key.

If there are two Senator Kennedys in the 110th Congress, Republicans will retain their majority. But if there’s a Senator Klobuchar, they’ll have to hope that the wind has not swept away control of the Senate.

Fortier is a research fellow at the American Enterprise Institute.