Several key Senate races are still a toss-up, according to poll tracking from RealClearPolitics (RCP) and FiveThirtyEight, making exact results difficult to predict.

Democrats will need 50 seats to retain control of the chamber, but a margin that then will require Vice President Kamala Harris to provide her casting vote on some legislation, as she has done over the past two years. That would allow Senate Majority Leader Chuck Schumer to remain in his job.

However, if Republicans end up with 51 seats or more, then they will form the majority and could prove a headache for President Joe Biden.

For live updates on the midterms, head over to Newsweek’s Live Blog: Who Won the Midterm Elections 2022?—Senate, House, Governor Results

RCP’s projection shows the GOP with 53 seats in the next Senate, more than enough to control the chamber and re-elect Minority Leader Mitch McConnell as the next majority leader.

In RCP’s Senate map, Republicans would win highly competitive races in Arizona, Pennsylvania, Georgia, Nevada and Ohio, while Democratic Senator Maggie Hassan would see off a challenge from Republican Donald Bolduc in New Hampshire.

The RCP forecast would see Republicans gain three seats and would be a significant victory for the party.

Though RCP’s projection shows Republicans with a Senate majority, their most-recent analysis of polls rates eight races as a toss-up: Arizona, Colorado, Georgia, New Hampshire, Nevada, Washington, Pennsylvania and Wisconsin.

RCP’s projection uses an adjusted poll average based on how much polls have previously underestimated support for the parties.

Larry Sabato’s Crystal Ball at the University of Virginia (UVA) Center for Politics also predicts success for Republicans, but forecasts that the GOP will control 51 seats in the next Senate, compared to 49 for Democrats.

In Crystal Ball’s projection, Republicans would win in the closely watched race in Pennsylvania, where Republican Dr. Mehmet Oz is locked in a tight contest with Democratic Lt. Governor John Fetterman.

While Pennsylvania leans Republican in that projection, the race in Georgia appears closer. Sabato’s Crystal Ball rates that race as likely Republican, which would see Herschel Walker defeat Democratic Senator Raphael Warnock.

However, Democratic Senator Catherine Cortez Masto would defeat a challenge in Nevada from Republican Adam Laxalt in Crystal Ball’s forecast; Democratic Senator Mark Kelly would win in Arizona; and Senator Hassan would also be re-elected.

Nonetheless, Republican J.D. Vance would defeat Democratic Representative Tim Ryan in Ohio.

A map prepared from the latest polling by the Trafalgar Group and shared to Twitter by the account Political Polls shows Republicans with 53 seats after the midterms and Democrats with 47 senators.

That projection shows Republican victories in Pennsylvania, Georgia, Ohio, Nevada and New Hampshire. The Trafalgar Group is a pollster for the Republican Party and enjoys an A- rating from poll-tracker FiveThirtyEight.

In its analysis of polls, FiveThirtyEight gives Republicans an 80 percent chance of having between 48 and 54 seats in the next Senate and rates the GOP slight favorites to win control of the chamber.

FiveThirtyEight’s analysis shows that the races in Pennsylvania and Nevada are toss-ups, while Walker, a Republican, is slightly favored to win in Georgia. Democratic Senators Kelly in Arizona and Hassan in New Hampshire are slight favorites to win in that analysis.

While the final forecasts look like good news for Republicans, key races remain close and final results could defy predictions.

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