It's a big win for Paul, who can stay in the political mix even if his sagging White House bid doesn't recover. The senator had threatened legal action to try to get around Kentucky's law prohibiting runs for both offices at the same time. If that had failed, he would have been forced to make a gamble that his campaign would rebound — a dicey bet given the large field.
It's a gamble his rival, Florida Sen. Marco Rubio, isn't taking. He has said he won't run for re-election and president, even though Florida's later filing deadline means he could have changed his mind. But given the competitiveness of the state with Senate control in the balance, he opted not to run.
In a way, the weekend decision is a win-win for both Paul and Kentucky. With the state moving up its vote to a March 5 caucus instead of a May primary, the Bluegrass State will get more political attention.
But whether Paul will even be on that ballot is an open question. The Kentucky caucus will not only come after the Iowa caucus and New Hampshire, South Carolina and Florida primaries, but also just after the so-called "SEC primary." That Tuesday, March 1, several Southern states and others will vote. If the first primaries don't winnow the field, this marathon voting day certainly will.
Right now, Paul's White House hopes have taken a hit. One of his most trusted aides and head of his superPAC, Jesse Benton, was indicted this month in an alleged Iowa endorsement payoff scheme. That case dated back to the 2012 presidential bid of the senator's father, former Texas Rep. Ron Paul. Rand Paul has also had trouble raising money and reported staff turmoil.
Polling hasn't been kind to Paul either, and he didn't have a breakout moment in this month's debate. The caucus will come at a high price for Paul, too — he's pledged to foot the bill for the change, which could be upwards of $500,000.
Democrats don't have a candidate to run against Paul in Kentucky yet, but they spent big to try to oust Senate GOP Leader Mitch McConnell last year, and lost. So for now, the odds are that Paul will be back in the Senate come 2017 and not the White House.