Republicans are guaranteed to keep control of the Senate after netting early victories by flipping four Democratic seats and winning a marquee race in Texas.



GOP candidates scored major victories in Indiana, Missouri and North Dakota, while several other toss-up races remain too close to call, paving the way for the party to potentially expand its 51-49 majority.

Businessman Mike Braun (R) unseated Sen. Joe Donnelly (D-Ind.) — marking the first red-state Democrat to lose on Tuesday and giving the GOP an early seat flip.

Three more Democrats followed: Sens. Heidi Heitkamp Mary (Heidi) Kathryn HeitkampCentrists, progressives rally around Harris pick for VP 70 former senators propose bipartisan caucus for incumbents Susan Collins set to play pivotal role in impeachment drama MORE (N.D.), Claire McCaskill Claire Conner McCaskillMomentum growing among Republicans for Supreme Court vote before Election Day Democratic-linked group runs ads in Kansas GOP Senate primary Trump mocked for low attendance at rally MORE (Mo.) and Bill Nelson Clarence (Bill) William NelsonDemocrats sound alarm on possible election chaos Trump, facing trouble in Florida, goes all in NASA names DC headquarters after agency's first Black female engineer Mary W. Jackson MORE (Fla.).



The red-state Democratic losses came after Republicans avoided a major upset in Texas, where Rep. Beto O'Rourke Beto O'RourkeJimmy Carter says his son smoked pot with Willie Nelson on White House roof O'Rourke endorses Kennedy for Senate: 'A champion for the values we're most proud of' 2020 Democrats do convention Zoom call MORE (D) shot into an early lead but was ultimately unable to overcome Sen. Ted Cruz Rafael (Ted) Edward CruzTrump argues full Supreme Court needed to settle potential election disputes Press: Notorious RBG vs Notorious GOP The Hill's Morning Report - Sponsored by Facebook - Washington on edge amid SCOTUS vacancy MORE (R).



Absent a last-minute upset in a seat controlled by Republicans, the three Democratic losses and the GOP win in Texas guarantees Republicans will hold onto the chamber, even with undecided races in Arizona and Nevada.



Democrats entered Election Day looking to defend seats in 10 states that Trump won in 2016, presenting them with an uphill battle to take back the Senate or maintain the GOP's slim majority.

ADVERTISEMENT

Sen. Jon Tester (Mont.) is the last vulnerable Democrat whose race has yet to be called. Though he remains in the lead against GOP challenger Matt Rosendale, the race has tightened as more precincts have begun reporting.



One race that will not be decided on Tuesday is a special election in Mississippi, where Sen. Cindy Hyde-Smith (R) was hoping to prevent a runoff election for her Senate seat.



Hyde-Smith and Democrat Mike Espy, as the top two candidates, will advance to a Nov. 27 runoff, but the outcome of that race will not determine control of the Senate.



Even with the Mississippi race undecided, Democrats could sweep the remaining battleground states and fall short, with Republicans holding a 52-47 majority in that scenario.

If Democrats sweep the remaining battleground states and Republicans ultimately win Mississippi, where Trump remains popular, that would give Republicans a 53-47 majority.



Democrats have gotten some good news on Tuesday night. Sen. Joe Manchin Joseph (Joe) ManchinThe Hill's Morning Report - Sponsored by Facebook - Trump, GOP allies prepare for SCOTUS nomination this week Trump meets with potential Supreme Court pick Amy Coney Barrett at White House Names to watch as Trump picks Ginsburg replacement on Supreme Court MORE (D-W.Va.) held off state Attorney General Patrick Morrisey in what was expected to be a competitive race.



Meanwhile, Sen. Tim Kaine Timothy (Tim) Michael KaineButtigieg stands in as Pence for Harris's debate practice Trump meets with potential Supreme Court pick Amy Coney Barrett at White House Names to watch as Trump picks Ginsburg replacement on Supreme Court MORE (D-Va.) and Sherrod Brown Sherrod Campbell BrownSenate Democrats release report alleging Trump admin undermined fair housing policies Bipartisan praise pours in after Ginsburg's death Emboldened Democrats haggle over 2021 agenda MORE (D-Ohio) easily won reelection, and voters in New Jersey decided to send Sen. Bob Menendez Robert (Bob) MenendezKasie Hunt to host lead-in show for MSNBC's 'Morning Joe' Senators ask for removal of tariffs on EU food, wine, spirits: report VOA visa decision could hobble Venezuela coverage MORE back to Washington for another six-year term.



But the defeat in Texas comes after Tennessee, another potential pickup, was quickly taken out of reach for Democrats with Rep. Marsha Blackburn Marsha BlackburnTaylor Swift on National Voter Registration Day: 'We need everyone' Democrats smell blood with new DHS whistleblower complaint Hillicon Valley: Election officials prepare for new Russian interference battle | 'Markeyverse' of online fans helps take down a Kennedy | GOP senators unveil bill to update tech liability protections MORE (R-Tenn.) defeating former Gov. Phil Bredesen (D) after holding a lead in the polls heading into Tuesday.



Democrats are still eyeing potential pick-ups in two western states with seats currently held by Republicans — Arizona and Nevada.

Rep. Kyrsten Sinema (D-Ariz.) had a slight lead over Rep. Martha McSally Martha Elizabeth McSallyTumultuous court battle upends fight for Senate Grassley, Ernst pledge to 'evaluate' Trump's Supreme Court nominee The Hill's Campaign Report: Biden goes on offense MORE (R-Ariz.) heading into Tuesday as they battle to succeed retiring Sen. Jeff Flake Jeffrey (Jeff) Lane FlakeJeff Flake: Republicans 'should hold the same position' on SCOTUS vacancy as 2016 Republican former Michigan governor says he's voting for Biden Maybe they just don't like cowboys: The president is successful, some just don't like his style MORE (R). If Sinema is victorious it would be the first time since 1988 that Arizonans have elected a Democrat to the Senate.



Meanwhile, Democrats held a lead among early voters in Nevada, where Democrats are feeling bullish about their ability to unseat Sen. Dean Heller Dean Arthur HellerOn The Trail: Democrats plan to hammer Trump on Social Security, Medicare Lobbying World Democrats spend big to put Senate in play MORE (R-Nev.), the only Republican senator up for reelection in a state won by Democratic presidential nominee Hillary Clinton Hillary Diane Rodham ClintonButtigieg stands in as Pence for Harris's debate practice Senate GOP sees early Supreme Court vote as political booster shot Poll: 51 percent of voters want to abolish the electoral college MORE in 2016.

Updated at 12:54 a.m.