Click here for the latest results from Super Tuesday.
Voters in 15 states are heading to the polls on Super Tuesday with 854 delegates up for grabs in Republican presidential primary elections and caucuses.
The first polling stations opened in Vermont at 6 a.m. ET, while the final polls won't close in Alaska until midnight ET. Results will start trickling in after 7 p.m. ET when the first polls close in Virginia and Vermont.
Former President Donald Trump, who has won all but one contest so far, cannot clinch the nomination outright but is looking to build an insurmountable lead against his only opponent, former South Carolina Governor Nikki Haley.
Heading into Super Tuesday, Trump has secured 276 delegates, while Haley has won 43. A candidate must win 1,215 delegates to win the Republican presidential nomination.
If Trump has a strong showing on Tuesday, he could lock up the nomination on March 12, when 170 delegates will be at stake in four primary contests in Georgia, Hawaii, Mississippi, and Washington.