 -- In 2017, Democrats not only held onto control of the governor's mansion in Virginia but nearly won back control of the state House of Delegates for the first time in almost 20 years. One year later, the party is defending the U.S. Senate seat held by former Vice Presidential nominee Tim Kaine, and eyeing a number of congressional districts in the Commonwealth they see as central to their task of re-taking the U.S. House in 2018. The GOP primary to take on Kaine is a marquee race, while Democrats will decide on nominees in those aforementioned House competitive House races. The most national attention will likely focus on Virginia's 10th Congressional District, which encompasses the suburbs to the south of Washington, D.C. There are six Democrats vying to take on Republican Rep. Barbara Comstock in a district Hillary Clinton won by 10 points in the 2016 presidential election. Virginia election results will be refreshed automatically every 60 seconds after polls close at 7 p.m. ET. There is no need to refresh the page to see the latest data. NOTE: In the unopposed races, we will receive no votes on Election Night, but the race will have a winner checked. Some House Districts are missing due to the fact they will nominate their candidate through a convention process and not in the primary; applies to Democrats CD 5 and Republicans CDs 3, 5, 6, 7 and 8.<doc-sep>Voters in Virginia, Nevada, Maine, North Dakota, and South Carolina head to the polls Tuesday for important 2018 primary elections. Nevada Democrats will formally pick their candidate in their bid to unseat Sen. Dean Heller. In Virginia, at least four House Republican incumbents should be vulnerable in November. Maine presents one of Democrats’ best chances to retake a governor’s mansion as they seek to rebuild the state-level control they lost under President Obama — and the state will be piloting a fancy new ranked-voting system, the first of its kind in the United States. Here is every June 12 primary election you need to know about, briefly explained. Virginia Virginia’s Second Congressional District: Democrats favor another female veteran to challenge Scott Taylor Who is the Republican? Rep. Scott Taylor, former state legislator, first elected in 2016. He voted for Obamacare repeal, the tax bill, and a 20-week abortion ban. Who are the Democrats? Elaine Luria is a former US Navy commander who now runs an art studio. She has earned the Democratic Congressional Campaign Committee’s Red to Blue imprimatur, which means the national party thinks she’s shown she can be a credible candidate. She also has the endorsements of Emily’s List and End Citizens United. On Tuesday, her only challenger is Karen Mallard, a schoolteacher who says that President Trump’s nomination of Education Secretary Betsy DeVos inspired her to enter the race. What’s the story here? The Cook Political Report considers this a Lean Republican race. But in 2016, though Taylor won handily, Trump beat Hillary Clinton by just 3 points. It’s a pretty diverse district too: 68 percent white, 20 percent black, 5 percent Asian, 5 percent Latino. Taylor is an incumbent, which gives him an advantage, but he is hardly an entrenched one. The left-leaning Public Policy Polling found Luria trailing by just 6 points in an April poll. Based on what we’ve seen in special elections and in Virginia last year, it wouldn’t even take much of a wave to make this race competitive. Virginia’s Fifth Congressional District: an open seat opportunity for Democrats after Tom Garrett stepped down Who is the Republican? Scandal-plagued Rep. Tom Garrett announced he would step down in late May. In place of a primary, under the circumstances, the local party nominated Denver Riggleman, a local distillery owner. He has promised to join the archconservative House Freedom Caucus if elected, of which Garrett was a member. Who are the Democrats? Like the Republicans, Democrats elected to have a nominating convention instead of a primary election. They picked Leslie Cockburn, a former reporter who supports Medicare-for-all. What’s the story here? Cook rates the Fifth District, which represents a big middle chunk of the state just west of Richmond, as Lean Republican and R+6. But the district did vote for a Democrat in the 2008 blue wave, and the GOP just lost the incumbency edge when Garrett retired. Then again, Trump won here by 10 points in 2016. This isn’t the suburban Republican, Never Trump kind of district propelling so much of the Democratic hopes in 2018. It’s a bit of a long shot, but Democrats could have a chance here in November, though it would be their biggest lift. Virginia’s Seventh Congressional District: Dave Brat suddenly finds himself in jeopardy Who is the Republican? Incumbent Rep. Dave Brat. He is a former college professor who famously ousted then-House Majority Leader Eric Cantor from the right in 2014. He’s one of the most conservative members of the House. Who are the Democrats? Abigail Spanberger is considered the favorite. She’s a former federal law enforcement officer and CIA operative and has amassed support from a lot of local leaders. She is facing Dan Ward, a retired military colonel. It’s worth noting that in Democratic primaries where the top choices are a man and a woman, women have been winning a lot. What’s the story here? Brat is an archconservative who knocked out an establishment Republican, but his district is changing. Trump won by 6 points here after Mitt Romney won by 11 in 2012. It swung 8 points toward Democrats in the governor’s race last year. There are a lot of younger, more affluent, and better-educated voters in the district, which covers parts of the Richmond suburbs. According to Cook, it’s an R+6 district, so this is far from a slam-dunk for Democrats. But party operatives insist they genuinely believe they could remove one of the furthest-right members of the House in a wave year. Virginia’s 10th Congressional District: Barbara Comstock is one of the country’s most vulnerable House Republicans Who is the Republican? Incumbent Rep. Barbara Comstock, first elected in 2014 and long pegged as one of 2018’s most vulnerable Republicans. A former Bush administration official, Comstock voted against Obamacare repeal but for the tax bill. It’s the latter that could land her in trouble, since the individual mandate repeal is being cited by insurers as a big reason for coming premium hikes for 2019. She does have a primary challenger: Shak Hill, a former Air Force officer and ex-Senate candidate running to her right. Comstock is taking him seriously enough to mount attacks against Hill. Who are the Democrats? State Sen. Jennifer Wexton is probably the frontrunner: She has name identification on her side, and she’s well-liked by many different factions. She can also run on Virginia expanding Medicaid. But she has some legitimate challengers: Alison Kiehl Friedman worked at the State Department under President Obama, Lindsey Davis Stover worked at the VA under Obama and on Capitol Hill, and Dan Helmer is a veteran running the furthest to the left. What’s the story here? The 10th sits near the top of Democratic targets in 2018. Cook pegs it actually D+1, and Clinton beat Trump here in the Washington, DC, suburbs by 10 points(!) in 2016. Everybody thinks this is a toss-up race. Comstock has defied the party on at least one major item — the House Obamacare repeal bill. But Democrats are going to pin premium hikes on her after she voted for the mandate repeal, and they say the tax bill particularly adversely affected Virginia by rolling back the tax exemption for state and local taxes. She has represented the area in one way or another for nearly 10 years, and she can expect a lot of support from national Republicans. If Democrats are going to take back the House, they absolutely need to beat Barbara Comstock and other Republicans like her. (Also, we are obligated to mention Nathan Larson, the independent candidate in this race, whom the Washington Post described as being “pro-incest, pedophilia, and rape.” He is not a real contender, but he’s gotten attention for his repulsive platform, if you want to call it that, as a self-identified “incel” candidate.) Virginia Senate: Tim Kaine is almost definitely going to win reelection Who is the Democrat? Incumbent Sen. Tim Kaine, first elected in 2012. Former governor and vice presidential candidate. Dad. Dork. Who are the Republicans? Libertarian state lawmaker Nick Freitas, former gubernatorial candidate Corey Stewart, and former lieutenant governor candidate E.W. Jackson. It’s quite a crew: Stewart keeps getting linked to white supremacists. Freitas has the backing of some high-profile libertarians, like Sens. Mike Lee and Rand Paul. Jackson thinks gay people are sick and yoga is Satanic, and, as a black man, he says he still opposes taking down Confederate monuments. Stewart was ahead in the one poll we’ve seen, but most voters said they were still undecided. What’s the story? Kaine is almost definitely going to win. Virginia has been trending strongly blue since Trump’s election, with Democrat Ralph Northam winning the governor’s race last year. Early polling has Kaine over 50 percent and leading any of his three potential Republican challengers by 20 points. Cook says this is a Solid Democrat race. But we had to mention it. Nevada Nevada Senate Democratic primary: Jacky Rosen readies to take on Dean Heller Who is the Republican? Sen. Dean Heller, first appointed in 2011. Heller’s voting record in the past year wouldn’t give you any indication that he’s running for reelection in an increasingly Democratic state. He’s voted with Trump almost 92 percent of the time. After announcing that he would oppose any Republican effort to repeal and replace Obamacare in June 2017, Heller went on co-sponsor an Obamacare repeal-and-replace bill with Sens. Lindsey Graham (SC) and Bill Cassidy (LA) that would have cut Nevada’s federal health care funding by $257 million. He voted for the GOP tax bill, which repealed the individual mandate and is expected to raise premiums in Nevada. Who are the Democrats? The clear frontrunner is Rep. Jacky Rosen. Her political history is very short. In 2016, as a political newcomer, she narrowly won a House race in Nevada’s Third Congressional District against Danny Tarkanian in her first bid for elected office. Her background is in computer programming and consulting, which she says has trained her to be a problem solver. Rosen has half a dozen challengers, but she’s far and away the favorite to emerge on Tuesday. What’s the story? Heller is the only Republican senator up for reelection in a state Clinton won in 2016. He has a 2-point net approval rating, and President Trump is underwater in the state. Nevada Democrats also have a big advantage: They have about 60,000 more registered voters in the state than Republicans do. Election prognosticators think this is a toss-up race, mostly on the strength of Heller’s incumbency, but the senator should be considered extremely vulnerable. Nevada governor: Democrats navigate a tense primary as they try to buck a nearly 20-year lockout from the governor’s mansion Who are the Democrats? Clark County Commissioners Steve Sisolak and Christina Giunchigliani are the favorites among a field of six, with things getting increasingly tense between the two in recent weeks. Ahead of the primary, Sisolak and Giunchigliani have traded barbs over everything from the mass shooting that took place in Las Vegas to a proposed bill that addresses the treatment of sex offenders. Polls give Sisolak — who’s amassed a $6 million war chest — a slight edge, but the bitterly contested race is still pretty close. Who are the Republicans? A whopping seven Republicans are in the running, and state Attorney General Adam Laxalt is expected to come out on top. Laxalt is known for backing the Trump administration’s hardline stance on immigration — signing on to a letter last year that sought to prevent Nevada from becoming a “sanctuary state” and joining a lawsuit in 2015 that challenged the Obama administration’s expansion of the Deferred Action for Childhood Arrivals program. Laxalt has also secured donations from big-ticket Republican names including Sheldon Adelson and the Freedom Partners Action Fund, a group that’s linked to the Koch brothers. His grandfather, Paul Laxalt, was previously a governor and senator for the state, and his father is late New Mexico Sen. Pete Domenici. What’s the story? Nevada hasn’t had a Democratic governor for nearly two decades, but the seat is currently rated as a toss-up by Cook Political Report. Since current Republican Gov. Brian Sandoval is term-limited out, Democrats are hoping to capture the momentum from Clinton’s 2016 victory — when she won the state by 3 points — and retake the seat. Nevada’s Third Congressional District: a long list of candidates vie for Rep. Jacky Rosen’s seat as she pursues the Senate Who are the Democrats? Philanthropist Susie Lee leads a field of seven in both endorsements and fundraising. Lee, who has been named to the DCCC’s Red to Blue list, has secured endorsements from incumbent Jacky Rosen, former Senate Minority Leader Harry Reid, and former Vice President Joe Biden. She previously ran unsuccessfully for Nevada’s Fourth District in 2016. Business exec Jack Love and computer programmer Michael Weiss are also among those on the ballot. Who are the Republicans? The most notable candidate and likely frontrunner is Danny Tarkanian, a businessman who filed for the House race after Trump asked him to clear the Senate primary for Dean Heller. There are nine total contenders including state Sen. Scott Hammond and former television reporter Michelle Mortensen. This wouldn’t be Tarkanian’s first time campaigning to represent this district if he wins the primary.<doc-sep>
(CNN) — Five states head to the polls on Tuesday in primary elections that will set up some of the most critical contests to determine control of Congress next year. Two of the most vulnerable senators – a Republican in Nevada and a Democrat in North Dakota – will have challengers by the end of the night. Add CNN's 2018 elections calendar Stay up to date on key election dates and other events, such as town halls and debates, as they get added throughout the year. Subscribe on your Google or Apple calendar. In South Carolina and Virginia, Republican voters will decide if they want to punish representatives who haven’t fully embraced President Donald Trump. Democrats in Nevada and Maine are picking candidates they need to turn the tide on GOP-controlled Washington. Here’s what you need to know: Polls close at 7 p.m. EDT in Virginia and South Carolina. In Virginia, Democrats are targeting a handful of seats to flip in November and Republicans will choose their nominee to challenge Democratic Sen. Tim Kaine. In South Carolina, Rep. Mark Sanford is facing an insurgent primary challenger who is attacking him for his criticism of Trump. Polls close at 8 p.m. EDT in Maine. The state will be the first in the nation to use ranked choice in statewide elections on Tuesday. Democrats feel good about the race to replace controversial Republican Governor Paul LePage, though the state’s unusual voting means even professional observers don’t know which Democratic candidate will win the nomination. State Attorney General Janet Mills and Iraq and Afghanistan wars veteran Adam Cote are both seen as strong Democratic candidates for the Fall. All polls are closed at 9 p.m. EDT in North Dakota. Republicans will most likely pick Rep. Kevin Cramer, the state’s sole representative in Congress, to challenge incumbent Sen. Heidi Heitkamp, one of the most vulnerable Democratic senator this November. Trump won North Dakota by 36 points in 2016. Polls close at 10 p.m. EDT in Nevada. Another competitive November election will be take shape here on Tuesday. Incumbent Sen. Dean Heller, considered to be the most vulnerable Republican senator this year, will most likely face Democratic Rep. Jacky Rosen, who is most favored to win her party’s nomination in a general election race CNN currently rates as a toss-up. Here’s a closer look at what to watch tonight: ANOTHER TRUMP CRITIC IN TROUBLE: Just one week after Republican Rep. Martha Roby was forced into a runoff in Alabama over her 2016 disavowal of Trump, South Carolina’s Sanford might face a similar fate. Sanford is facing a strong primary challenge from state Sen. Katie Arrington, who has attacked him for criticizing Trump and has alluded to his adulterous past, saying in an ad that “it’s time for Mark Sanford to take a hike — for real this time.” Sanford only won re-nomination by 4,000 votes in 2016, but he has also demonstrated a remarkable ability to weather political storms and controversies over the years. WILL PARNELL WIN? Sanford is not the only politician in hot water in South Carolina. In the state’s 5th Congressional District, embattled Democrat Archie Parnell – who narrowly lost a 2017 special election – remains on the ballot, despite recently admitting to domestic abuse in the 1970s, news which rocked his campaign and likely spoiled a long-shot Dem pick-up opportunity if Parnell advances. MCMASTER OF HIS OWN FATE: The Palmetto State is home to one of the most compelling gubernatorial contests of the year. Republican Gov. Henry McMaster — who endorsed then-candidate Trump in January 2016 — earned a Trump Twitter endorsement in the final weekend heading into the primary. He faces strong challengers in Catherine Templeton and John Warren, among others. McMaster must win 50% of the vote or more in order to avoid what would be an embarrassing runoff. On the Democratic side, state Rep. James Smith – endorsed by Joe Biden – is seen as the one Democrat who can pull off the upset in deep red South Carolina, should a “blue wave” extend that far south. STRONGER ALONE: After losing for Vice President in 2016, Kaine is uncontested in the Democratic primary in Virginia for his Senate re-election. The Republican primary for the seat has been another race to the right between 2017 gubernatorial candidate Corey Stewart, state Delegate Nick Freitas, and pastor E.W. Jackson, the Virginia GOP’s 2013 nominee for lieutenant governor.