However, given the state's unusual election system in which the two top vote-getters move on to the general election in November, regardless of party affiliation, Democrats fear they may give Republicans the upper hand in some districts where they have a glut of candidates.
More than 3.5 million votes had been counted in each of those five races Wednesday morning.
For the first time in a decade, more Democrats than Republicans have registered to run in Texas legislative races this year-bolstering speculation that the deep red state could be turning purple.
Republicans have been in a tailspin for years in California, where a diversifying population has grown increasingly Democratic in its leanings. In one, voters favored Hillary Clinton, giving Democrats hope that it could flip in 2018. The Democratic Party "tried to winnow out some of the candidates, but the same excitement and energy that led them to run in the first place makes them unlikely to listen to the national party", DeSipio said.
LOS ANGELES-John Cox, a Republican business owner who has tried and failed for almost two decades to win elected office, snagged a spot in the November runoff for California governor with the help of U.S. President Donald Trump, but that support could hurt him in the winner-take-all race with Democrat Gavin Newsom.
Overall, it was a big night for women, as female candidates for governor advanced, including Democrat Michelle Lujan Grisham in New Mexico and Republican Kristi Noem in South Dakota. "Democrats have done a good job of turning enthusiasm into a large number of candidates, of turning enthusiasm into fundraising", Gonzalez said.
And in New Mexico, Democrat Deb Haaland's win puts her on track to become the nation's first Native American congresswoman. And so the problem may be that Democrats have so many people running this time around, that it could split the vote and Republicans could end up benefiting.
Rosendale's win means the two best flat-top haircuts in politics will face each other in a state where Trump won big in 2016 and where he has made Tester a frequent target. In fact, he hasn't been a Republican all that long. The elections in California, Iowa, New Jersey, Montana, New Mexico, Mississippi and Alabama will shape the midterm battles that will redefine politics in the United States in the next few months. The two will face off in November.
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Health care could also play a role in several of California's congressional races. The party won't come close to the turnout figures for the 2016 primary, when the Democratic vote in some districts more than doubled.
Much of Tuesday's drama focused on women, including the former federal prosecutor and Navy pilot Mikie Sherrill, who bested a field of rivals in New Jersey for the Democratic nomination to replace the retiring Republican Representative Rodney Frelinghuysen.
"We have truly built a movement for change here in the 48th Congressional District and I look forward to defeating Dana Rohrabacher and restoring honesty and integrity to this office", Rouda said. He'll face Republican attorney Mark Meuser, who came in second.
In the race for termed-out GOP Supervisor Bill Horn's North County seat, Republicans were the ones with a voter registration advantage.
In swing states such as New Jersey, Democrats are trying to capitalize on the anti-Trump sentiment there to make advances in the House.
But it was far from a victory for the party.
National Democrats spent more than $7 million trying to curb and fix the damage inflicted by Democrats attacking each other in districts opened by retiring Republican Reps. The party celebrated when Democratic state Sen. Jeff Van Drew and former assistant Secretary of State Tom Malinowski.
"All that energy, which is still building, is going to lift Democrats up and down the ballot", she said. It was a clear sign that a strong challenger might have been able to unseat Menendez. In the last four midterm elections where the president's approval rating was 46 percent or lower, his party lost an average of 40 seats.
Why does this small seat in Missouri matter nationally? Democrats loved this idea when they adopted in 2009, but they may not be loving it so much tonight. Some of the contests also turned personally nasty, potentially turning off voters. The Republican nomination of Donald Trump, despite his tepid support from Republican elected officials and his frequent breaks from Republican orthodoxy, defied the scholarly consensus about how "party elites" are supposed to have sway over their voters.