Story highlights The brash billionaire and GOP front-runner fired off several attacks against Jeb Bush, Hillary Clinton and his latest foe: former President Bill Clinton

Trump had recently said that the former president's alleged abuse of women and extramarital affairs were "fair game"

Washington (CNN) Donald Trump is picking up where he left off in 2015 when it comes to his favorite Twitter targets.

The brash billionaire and GOP front-runner fired off several attacks against Jeb Bush, Hillary Clinton and his latest foe : former President Bill Clinton.

Early in the morning, Trump called the former Florida governor a "sad case" with "no chance."

".@JebBush is a sad case. A total embarrassment to both himself and his family, he just announced he will continue to spend on Trump hit ads!" Trump tweeted.

.@JebBush is a sad case. A total embarrassment to both himself and his family, he just announced he will continue to spend on Trump hit ads! — Donald J. Trump (@realDonaldTrump) January 2, 2016

He then hit the former secretary of state over her opposition to his call for a temporary ban on Muslims entering the United States.

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