Both Democrats and Republicans have 48 seats in the Senate and four seats remain undecided with those races still outstanding.
WASHINGTON -- The 2022 midterm elections are shaping up to be some of the most consequential in the nation's history, with control of Congress at stake.
All 435 seats in the House and 35 of 100 seats in the Senate are on the ballot, as well as several influential gubernatorial elections in battleground states like Arizona, Georgia, Pennsylvania and Wisconsin.
In the Georgia Senate race, ABC News reports no candidate will receive more than 50% of the vote, meaning there will be a runoff election between Democrat Raphael Warnock and Republican Herschel Walker on Dec. 6. This race is one of the most competitive in the country and will likely determine which party will control the Senate.
There are two other Senate races -- Alaska and Nevada -- as well as a number of House races that have yet to be called. Most are separated by razor-thin margins and all will come down to counting the vote.
Democrats are defending their narrow majorities in both chambers. Republican control of either the House or Senate would be enough to curtail most of President Joe Biden's legislative agenda and would likely result in investigations against his administration and even his family.
Voters in battleground Michigan enshrined abortion rights in the state constitution, joining reliably Democratic California and Vermont in taking that step.
An anti-abortion measure in Kentucky was too early to call.
The Tuesday ballot measures came months after the Supreme Court overturned Roe v. Wade and the constitutional right to abortion it guaranteed to women nationwide. The decision in June has led to near-total bans in a dozen states.
Voters have approved recreational marijuana in Maryland and Missouri and rejected it in Arkansas and North Dakota. The measure also is on the ballot in South Dakota.
The elections are seen as a test of legalization's support in even the most conservative parts of the country.
The state voting follows moves by President Joe Biden toward decriminalizing marijuana.
Heading into the election, recreational marijuana was legal in 19 states, and polls have shown opposition to legalization softening.
The Associated Press and ABC News contributed to this report.