He can't run for both Senate and President at the same time in Florida. He maybe just raising money for his Senate race. He was originally being groomed by the Bush machine for a run as president but that fell apart when he ran for the Senate. He found himself on the outs with JEB.
The nightmare scenario, both for Washington, its Gulf Arab allies, and for Yemen, is that the country erupts into a civil war pitting the Shia Houthis - suspected of being backed by Iran - against Sunni tribes backed by al-Qaeda.