Democratic Senator Mark Kelly defeated Republican venture investor Blake Masters in his race for reelection on Friday in the pivotal swing state of Arizona, putting his party one victory away from securing control of the chamber for the remaining two years of Joe Biden's presidency.

The Democratic party can keep control of the Senate by winning either the Nevada election, which is still too close to call, or the Georgia runoff at the end of the month. Vice President Kamala Harris will cast the deciding vote. To gain a majority, Republicans must now prevail in both of those contests.

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Republicans targeted a few races, including the one in Arizona, in their effort to seize control of the Senate, which is currently tied 50-50. It was a test of the strides Kelly and other Democrats had made in a state that the GOP had previously consistently controlled. Kelly's victory indicates that Democratic success in Arizona under Donald Trump's presidency was not an anomaly.

It was still too early to declare a winner in Friday night's closely watched governor's race between Democrat Katie Hobbs and Republican Kari Lake. Democratic candidate Adrian Fontes defeated prominent 2020 election skeptic Mark Finchem in the race for secretary of state.

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Kelly, a former NASA astronaut with four space flights, is married to former US Republican Gabby Giffords, whose recovery from a gunshot wound to the head sustained in a failed assassination attempt in 2011 that left six people dead and 13 injured inspired the country. A group advocating for gun safety was later co-founded by Kelly and Giffords.

The majority of Kelly's 2022 campaign revolved around his commitment to abortion rights, Social Security protection, drug price reductions, and securing a reliable water supply amid a drought that has reduced Arizona's cut of Colorado River water.

Masto narrows in on Laxalt in Nevada Senate race

With the control of the US Senate at stake, election officials in Nevada finished their laborious ballot tally on Friday, one day before the deadline for accepting late mail-in votes on Saturday.

Democratic Senator Catherine Cortez Masto was running barely behind Republican Adam Laxalt, but with the remaining uncounted ballots mainly coming from the state’s urban cores, she expressed optimism to overtake Laxalt.

Laxalt, meanwhile, has steadily predicted he’ll stay in the lead as the count drags on.

“We are doing everything in our power to move ballots forward just as quickly as we can,” Joe Gloria, the registrar in Clark County, which includes Las Vegas, said at a press conference Friday.

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Nevada is one of three uncertain races that will determine which party controls the chamber because the Senate is evenly divided.

Democratic Raphael Warnock and Republican Herschel Walker will face off in a runoff election in Georgia in December. If either party wins the state plus the Arizona contest, it will already hold a majority. Additionally, if the Arizona and Nevada seats are split between parties, control of the Senate will be decided in Georgia.

Republican Sheriff Joe Lombardo defeated Democratic Governor Steve Sisolak in another crucial race on Friday night.

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