The race for the White House is heading west tonight, as Arizona and Utah voters will make their voices heard in both races. 

Idaho will also make its choice on the Democratic side. 

As always, Fox News Channel will have you covered as the returns come in. 

Bret kicks off the primetime coverage at 6:00pm ET with Special Report, followed at 7:00 by On the Record, as both programs also cover the latest developments out of Brussels.

Bret will have reaction from Rep. Michael McCaul (R-TX), House Homeland Security Committee Chairman.

Then at 8:00, Bill O'Reilly assesses the latest terror attack and talks to Sen. Ted Cruz.

America's Election Headquarters - anchored by Bret Baier, Martha MacCallum and Bill Hemmer - gets underway at 9:00pm ET, followed by Hannity at 10:00pm ET.

Bret, Martha and Bill will take you through the next two hours and Eric Shawn and Heather Childers will be live with continuing coverage overnight, starting at 1:00am ET. 

Here's where the Republican race stands and what's at stake tonight:

Donald Trump has moved to more than halfway toward the 1,237 needed to secure the nomination. He leads Ted Cruz by more than 250 delegates. 

58 delegates are at stake in Arizona and the winner will take all of them. There have been relatively few polls out of the state, but the most recent have shown Trump with a double-digit lead.

And in Utah, 40 delegates are up for grabs in a caucus. Ted Cruz is expected to come out ahead and a candidate can take home all 40 delegates by winning at least 50% of the vote.

On the Democratic side, Hillary Clinton is looking to continue her momentum following big victories last week. She has amassed more than 1,600 delegates, almost twice the total of Bernie Sanders.

75 delegates are up for grabs in Arizona, 33 in Utah and 23 in Idaho. 

Stay with Fox News Channel throughout the night and into the morning to see how it all shakes out!

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