(CNN) -- After a campaign season that seems to have gone on for years, the day has finally arrived. On Tuesday, America will select a president of the United States, about a third of the Senate and a new House of Representatives. We invited CNN contributors to tweet their predictions. One of the first CNN contributors to announce his prediction on Twitter was Alex Castellanos. In his latest column, he explains why he's betting fellow Republican Mitt Romney will win. Democratic strategist Paul Begala disagrees with Castellanos' prediction. Right after the first presidential debate in which some were underwhelmed by President Barack Obama's performance, Begala remarked, "There is no doubt Romney had a good night. But I strongly doubt whether it was good enough." Begala's tweet reflects his prediction of a narrow win for Obama.
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CNN contributors tweeted their predictions on who will win on Tuesday
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Hilary Rosen predicts President Obama will be re-elected with 276 electoral votes
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Ari Fleischer thinks Mitt Romney will win with a minimum of 271 electoral votes
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Readers: Who do you think will win? Offer us your predictions on @CNNOpinion
@placeholder, a Democratic strategist, is positive about the outcome for her party.