2012 nominee's decision opens up new opportunities for "next generation" of candidates.
Steve Munisteri, chairman of the Texas Republican Party, is joining the senator's team.
The N.C. Republican only had $700K on hand at the end of last year.
Romney is set to hold a conference call with supporters at 11 a.m.
The secretary of State will gladly pay the ticket, a spokesman said.
He tweeted a fake phone call between two actors dinging his potential 2016 rivals.
The trips could open Clinton to attacks.
David Kochel, who headed Romney's past Iowa efforts, is in line to manage Bush's campaign.
The Vermont senator is considering a challenge to Clinton from the left.
He's launching the “Security through Strength" committee as he weighs a White House bid.