Alaska’s nonpartisan Senate primary will offer a rare opportunity to test the strength of the two leading candidates, Dan S. Sullivan, the Republican incumbent, and former Rep. Mary Peltola, a well-funded Democrat, as they face off months before November. And Northern California voters will choose a replacement for former Rep. Eric Swalwell, who resigned in the spring after allegations of sexual misconduct. Here’s what to watch on Tuesday, a busy primary day from coast to coast. Notable Senate race? Alaska has nonpartisan Senate primaries, and the top four candidates will advance to the general election. That means Sullivan, 61, and Peltola, 52, will face off, along with a host of long-shot contenders, on Tuesday’s ballot. Sullivan and Peltola are expected to advance Tuesday, but their vote percentages will be closely watched as a reflection of who is ahead in the general election. Also in question is whether Dan J. Sullivan, a former educator with little political experience, will win a spot on the general election ballot. Republicans are concerned that voters will mistakenly vote for Dan J. Sullivan thinking they are voting for Senator Sullivan, which could propel Peltola to victory in November. In Florida, does Debbie Wasserman Schultz hold up? Rep. Debbie Wasserman Schultz of Florida, an 11th-term congresswoman and former chairwoman of the Democratic National Committee, is trying to escape a crowded primary. His seat was eliminated when Republican state lawmakers gerrymandered the state’s congressional map in the spring, as part of a partisan coast-to-coast redistricting battle. Wasserman Schultz, 59, who is white, is now running in a historically black district, against four black Democrats. One of them, Elijah Manley, 27, an educator who describes himself as a democratic socialist, has won the support of Rep. Ro Khanna, D-Calif., and is in for a surprise. What about Jared Moskowitz? Rep. Jared Moskowitz, a second-term Democrat, is also trying to capture a new district after his old one was eliminated in the redistricting wars. Like Wasserman Schultz, the moderate Moskowitz, 45, is trying to fend off a younger rival on the left. He is running against Oliver Larkin, 34, a democratic socialist and union organizer. The races involving Wasserman Schultz and Moskowitz could help determine whether any left-wing primary waves are coming to Florida. Mills, who is running for re-election in a district northeast of Orlando, is under investigation by the House Ethics Committee. Last year he was investigated by Washington, D.C., police after a woman filed an assault complaint, although no charges were filed. And his ex-girlfriend was also granted a protective order. This month, two Republican members of the Florida House of Representatives, Anna Paulina Luna and Mike Haridopolos, endorsed one of their rivals, Ryan Elijah, 54, a former local Fox TV news anchor. But Mills, 46, who has denied any wrongdoing, maintains the endorsement of President Trump, a powerful force in the Republican primaries. Will Alexander Vindman become the Democratic Senate candidate? The quintessential swing state has swung to the right over the past decade, and political analysts give Democrats a long shot at winning the Senate race there in the fall. But some Democrats hope that Alexander Vindman, 51, one of the key witnesses in Trump’s first impeachment trial, will give their party a chance. Mr. Vindman, a former Army lieutenant colonel, has proven to be a great fundraiser. But first, to advance to the general election, he must fend off a Democratic socialist, state Rep. Angie Nixon, 42, of Jacksonville, who has won the endorsement of progressive members of Congress and the popular children’s entertainer Ms. Rachel. The winner of the Democratic Senate primary is expected to face Sen. Ashley Moody, a Republican who was appointed to former Secretary of State Marco. Blond. Who will replace Swalwell in California? Four months ago, Swalwell resigned from Congress, giving up his Bay Area seat after allegations of sexual assault, which he denied. Now voters in the quiet suburbs of San Francisco will go to the polls to elect Swalwell’s replacement. The race pits state Sen. Aisha Wahab, 39, a progressive backed by the California Democratic Party, against Melissa Hernandez, 51, a moderate backed by main AIPAC super PAC. Wahab led Hernández by 26 percentage points in a crowded nonpartisan primary in June. But since then the race has been flooded with cash.
