One is Sen Heidi Heitkamp's seat in North Dakota.
Judging by Menendez's tepid primary performance on Tuesday against an unknown and unfunded challenger, Hugin's strategy appears to have a chance of working.
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The candidates who win Tuesday's primaries will run in the November general election.
Alison Friedman, a former State Department official who worked to combat human trafficking, said in an interview that she's "always been motivated by standing up to abuses of power", before accusing Trump of doing the same. Scott Hammond and former reporter Michelle Mortensen.
Only 15 of the 99 competitive seats are now held by Democrats, while 84 are held by Republicans. But an influx of Latinos and other blue-leaning voters since then has given Democrats a lead of 97,325 registered voters as of May compared with a Republican lead of 3,250 registered voters in 1998, according to Nevada secretary of state data.
"I think it's in some ways a bit of a thermometer about how Republicans in the state of Virginia are going to either embrace or move away from the President, because Corey Stewart has embedded himself and wrapped his arms around the administration", said NBC12 Political Analyst and VCU professor Dr. Deirdre Condit. Geoffrey Skelley of Larry Sabato's Crystal Ball writes, "Comstock is a prodigious fundraiser and has a history of outpacing the partisan lean of districts she has represented, but the district's Democratic shifts in 2016 and 2017 show why she is one of the Democrats' foremost targets in 2018".
Before casting a ballot, Virginia voters in the primary election must declare whether they want a Republican or Democratic ballot.
President Trump urged South Carolina Republicans to vote U.S. Rep. Mark Sanford out of office Tuesday, tweeting that the three-term congressman was "better off in Argentina" - a reference to a sex scandal that forced Sanford to resign as governor.
In the Seventh Congressional District, incumbent Republican Rep. Dave Brat will face off against the victor of a Democratic primary between former Central Intelligence Agency operative Abigail Spanberger and retired Col. Dan Ward. The victor will face incumbent Rep. Dave Brat (R - 7th District).
As recently as the 1990s, Democrats and Republicans were fairly even divided in Nevada, a state that had supported Republican presidents including Ronald Reagan, George H.W. Bush and his son, George W. Bush.
Belangia is referring to the historic number running in Greenville and Spartanburg's House District 4: 13 republicans and five democrats.
Democrats are also waging closely watched contests in Hampton Roads and central Virginia. Ed Gillespie won this district last November 54%-45%.
Democrats hope voter dissatisfaction with President Trump in a state that has been trending blue will help them flip several seats held by Republicans.
If Democrats have any shot of winning control of the Senate, they'll need to successfully defend Sen. In 2016, Hillary Clinton carried the district by 10 points over Donald Trump in the presidential race. In suburban Richmond's seventh district, former Central Intelligence Agency officer Abigail Spanberger, who was endorsed by the pro-choice fundraising group Emily's List, faces former Marine Corps pilot Dan Ward in the Democratic primary.