The gubernatorial recall vote in Wisconsin highlights Tuesday's elections. Five other states are conducting presidential primaries, although Republican Mitt Romney and Democrat Barack Obama already have collected enough delegates to win their parties' nominations. Those races and other highlights of voting:
CALIFORNIA (polls close at 11 p.m. EDT)
Senate: Twenty-four names are on the primary ballot. Under a new primary system, the top two choices will compete in the general election regardless of party affiliation. Democratic Sen. Diane Feinstein is expected to be one of them.
Ballot initiative: Voters will weigh in on a proposal to raise cigarette taxes by $1 a pack to fund cancer research.
MONTANA (polls close at 10 p.m. EDT)
Senate: Rep. Denny Rehberg is expected to win the Republican primary to challenge Democratic Sen. Jon Tester. Rehberg faces token primary opposition and Tester is unopposed.
Governor: Republicans hoping to retake the governor's mansion after eight years under Democrat Brian Schweitzer have to choose from a large field that includes former Rep. Rick Hill. Democrats are expected to nominate Attorney General Steve Bullock.
NEW JERSEY (polls close at 8 p.m. EDT)
Senate: Democratic Sen. Bob Menendez is unopposed in the party primary. Republican state Sen. Joe Kyrillos faces three relatively unknown challengers and is expected to oppose Menendez in the general election.
House: In the redrawn 9th Congressional District, two House Democrats, Rep. Steve Rothman and Rep. Bill Pascrell, are competing in the heavily Democratic district. In the 10th Congressional District, six candidates are on the ballot to replace the late Rep. Donald Payne, whose seat is expected to remain with Democrats this fall. Newark City Councilman Donald Payne Jr. hopes to succeed his father.
NEW MEXICO (polls close at 9 p.m. EDT)
Senate: Former Rep. Heather Wilson is expected to win the Republican primary to fill the seat of retiring Democratic Sen. Jeff Bingaman. Rep. Martin Heinrich and state auditor Hector Balderas are seeking the Democratic nomination.
House: A close race is expected in the Democratic primary for Albuquerque's 1st Congressional District, which is being vacated by Heinrich. In a three-way race are former Albuquerque Mayor Marty Chavez, state Sen. Eric Griego and Bernalillo County Commissioner Michelle Lujan Grisham. The winner will face former Republican state Rep. Janice Arnold-Jones.
SOUTH DAKOTA (polls close at 9 p.m. EDT)
House: In the Democratic primary for the state's only House seat, Matt Varilek, former economic development director to Sen. Tim Johnson, faces Jeff Barth, a retired telephone company technician and county commissioner. The winner will oppose Republican Rep. Kristi Noem.
WISCONSIN (polls close at 9 p.m. EDT)
Recall: Republican Gov. Scott Walker faces a recall vote, just the third for a governor in U.S. history. His Democratic opponent is Milwaukee Mayor Tom Barrett, who lost the gubernatorial election to Walker in 2010. Also facing recall votes are Republican Lt. Gov. Rebecca Kleefisch and three GOP state senators. A fourth GOP state senator was forced into a recall, but she resigned; an election to fill that seat also is Tuesday.