WASHINGTON (AP) -- Three-time incumbent Herb Kohl faces only token Republican opposition in his quest for a fourth term in the U.S. Senate.

He faces a challenge from Bear Creek farmer and lawyer Robert Lorge, who received just four percent of the vote when he ran for the nomination in 2004 against Tim Michels.

Michels weighed taking on Kohl this time around, but it was Tommy Thompson's interest in the seat and his indecisiveness that caused Michels to step back.

By the time Thompson announced he would not run for the Senate, it was already June -- too late for Michels to put together a serious campaign.

The state GOP was also stymied by Kohl's personal wealth, making it an uphill battle for any potential challenger.

Kohl is a multimillionaire who owns the Milwaukee Bucks and has put about $4.6 million of his own money into the race. He refuses to accept political action committee donations.

Kohl has tended to the home front, especially as it pertains to dairy policy. He helped defeat the renewal of the Northeast Dairy Compact, a program opposed by Midwestern dairy farmers, and supported the replacement Milk Income Loss Contract, which pays dairy farmers cash when prices fall below a certain level. Wisconsin dairy farmers have been the biggest beneficiaries of that program.

US SENATE-BIO BOXES

NAME -- Herb Kohl, Democrat

AGE -- 71

EDUCATION -- Bachelor's degree, University of Wisconsin-Madison, 1956; Masters in Business Administration, Harvard, 1958.

CAREER -- President, Kohl Corp., 1970-79; Owner, Milwaukee Bucks basketball team, 1985-present; U.S. senator, 1989-present.

FAMILY -- Single.

NAME -- Robert Gerald Lorge, Republican

AGE -- 47

EDUCATION -- Bachelor's degree, University of Wisconsin-Madison, 1982; studied at University Freiburg in Germany and Lancaster University in England; law degree, Marquette University, 1985.

CAREER -- Attorney, with offices in Madison and Bear Creek; farmer; real estate broker; won the GOP nomination for secretary of state in 2002 and lost to incumbent Democrat Doug La Follette. Lost GOP Senate primary in 2004 to Tim Michels.

FAMILY -- Married.

NAME -- Rae Vogeler, Green Party

AGE -- 50

EDUCATION -- Associate and electrical engineering degree, Milwaukee School of Engineering, 1986; bachelor's degree, social work, University of Wisconsin-Milwaukee, 1980.

CAREER -- Freelance technical writer and small business owner; previously worked as a truck driver, factory worker, nurse's aide and waitress.

FAMILY -- Married, two children.

NAME -- Ben Glatzel, independent

AGE -- 44

EDUCATION -- Milwaukee Area Technical College, industrial engineering associate degree program, 1985.

CAREER -- District manager, Milwaukee Water Works. Also worked as water project coordinator, public works inspector and drafting/engineering technician.

FAMILY -- Married, four children.