Hot 100 March Madness 2013: Vote In The Finals!
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Cast your ballot for the best Top 5 single of the past year.

Thirty-two songs entered, and now, only two stand: after four rounds of Billboard.com's Hot 100 March Madness, the fans have helped a pair of pop divas their respective brackets and reach the Finals. Will.i.am & Britney Spears' "Scream & Shout" and Kelly Clarkson "Stronger (What Doesn't Kill You)" are your favorite Top 5 singles of the past years, and it's time for the pop hits to face off against each other to see who will be crown the Hot 100 March Madness 2013 champion!

To choose the winner of this year's competition, check out the updated bracket of songs, and vote for your favorite track in the head-to-head match-up below!

FOUR

From April 1, 2012 through the charts dated March 9, 2013, there have been exactly 32 songs that appeared in the Top 5 of the Hot 100 chart. The match-ups within this year's Hot 100 March Madness bracket were decided arbitrarily, with those 32 hit singles placed in random competition in a quest to follow last year's winner, Britney Spears' "Hold It Against Me." Click here to see the original bracket.

On Thursday, Mar. 28, a new Hot 100 March Madness champion -- the Top 5 song that you think was the hottest single of the past year -- will be crowned. Hundreds of thousands of votes have come in, and on Thursday, the final round of voting ends. Be sure to make your voice heard in time!

Looking back at the Final Four of this year's Hot 100 March Madness, Will.i.am & Britney once again combined to wallop another opponent, this time P!nk's "Blow Me (One Last Kiss)." Although the voting was close when the fourth round of voting began, "Scream & Shout" pulled away later in the week, and ended up with 70 percent of the final vote. That means that Spears, who won last year's Hot 100 March Madness, still has a shot at repeating and earning a second consecutive title.

First, however, Will.i.am and Britney Spears will have to surpass Kelly Clarkson, whose No. 1 smash "Stronger (What Doesn't Kill You)" breezed by Rihanna's "Diamonds" in the Final Four. Earning 57 percent of the final vote, "Stronger" won its fourth consecutive match-up to earn a spot in the Finals.

So who will it be -- Kelly Clarkson, or Will.i.am & Britney Spears? You only have until Thursday to weigh in! Vote now for your favorite track below, and discuss the competition in the comments section.

Voting has ended! CLICK HERE to see who won Hot 100 March Madness 2013.