Primary voters will set the stage today for high-stakes U.S. Senate battles in New Hampshire, Rhode Island and Minnesota, the last expected to feature a rematch between Democrat Paul Wellstone and Rudy Boschwitz, the Republican he ousted six years ago. Eight states in all hold primaries on this last big day of voting before November. Primaries for governor are on tap in Vermont and New Hampshire, and congressional races top the ballot in Arizona, Connecticut, New York and Wisconsin.

The primaries come as Democrats optimistic about President Clinton’s chances for reelection look to regain the ground they lost in 1994 in Congress. The GOP now holds a 53-to-47 edge in the Senate.

In New Hampshire, no Democrat has been elected to the Senate in two decades, but the national party considers Senator Bob Smith vulnerable and has made denying the Republican a second term a priority. Smith has been criticized for displaying a plastic fetus and graphic photos and drawings in a Senate floor speech opposing partial-birth abortions and for going on for 45 minutes on the danger to people that elephants posed during a circus performance at the U.S. Capitol in April. The two Democrats competing to face Smith are businessman John Rauh, who lost the Senate race in ’92, and former Congressmember Dick Swett. In ’90, Swett became the first Democrat elected in the 2nd Congressional District in seven decades.

In Rhode Island, Democrat Congressmember Jack Reed and Republican state Treasurer Nancy Mayer are expected to easily win their respective primaries in the race to succeed Democratic Senator Claiborne Pell, who is retiring after six terms.

Minnesota is also holding Senate primaries in both parties, but most see it as a formality between November’s rematch between Wellstone and Boschwitz. Wellstone, the only senator up for reelection who voted against the welfare repeal measure, had been seen as highly vulnerable. However, a recent newspaper and TV poll found him leading Boschwitz; 46% favored Wellstone, 37% favored Boschwitz in the poll, which had a margin of error of 4 percentage points.

In other voting, New York’s 19th Congressional District offers a bitter GOP primary rematch between incumbent Congressmember Sue Kelly and Joseph DioGuardi. Kelly, who supports abortion rights, has the support of Speaker Newt Gingrich and the House’s GOP leadership, while DioGuardi has campaigned hard on his opposition to abortion and his conservative credentials. In ’94, Kelly defeated DioGuardi and five other men in the GOP primary for the open seat.

And Wisconsin Congressmember Steve Gunderson, one of the only two openly gay House Republicans, is retiring from the 3rd District in the western part of the state. A write-in effort is being mounted by his supporters, although Gunderson has said he does not endorse it. In Arizona, Congressmember Jim Kolbe, the other openly gay House Republican, recently outed, faces minor primary opposition. Kolbe revealed his homosexuality this summer when a gay magazine said it planned to out him because of his vote against recognizing same-sex marriages. The Senate will take up that issue today.

And New Jersey’s Senate candidates are getting some outside help that advances their campaign themes and saves them some cash in what is the nation’s most expensive race. They’re called issue ads, and they focus on Republican Dick Zimmer or Democrat Robert Torricelli for their House voting records. Only at the end do the ad sponsors give a phone number urging voters to contact the congressmen about an issue before Congress goes home to campaign in October. The ads are independent of the campaigns and never mention the Senate race. But the commercials, aired by the Republican National Committee, the Sierra Club and New Jersey Citizen Action, echo the strategies of both campaigns. For Zimmer, the RNC television ad hits Torricelli as a liberal who voted for what Republicans always call the biggest tax increase in American history. The Sierra Club radio ad trumpets Torricelli’s environmental record, the Citizen Action radio ad trashes Zimmer’s prior votes in anticipation of this month’s vote on funding environmental enforcement.