For now, he's choosing to pony up.
Paul's political future rests partially in the hands of nearly 350 Republican officials in Kentucky, who will decide Saturday whether to approve a costly plan that would allow him to run in Kentucky for president and the U.S. Senate simultaneously—and possibly salvage his chances of staying in electoral politics after 2016.
The proposal, which acts as a work-around of a state law that forbids candidates in Kentucky from running for two federal offices at the same time, would establish a presidential caucus in early March in addition to the state primary scheduled two months later.
If it's approved, Paul would be allowed to run for president in Kentucky during the March caucus and also for his Senate seat in the May primary. But if it's turned down, Paul would be forced to give up his Senate seat in exchange for a chance to win any presidential delegates from his home state. (The state legislature shot down a bill last year that would have changed the law so candidates could appear twice on a the same primary ballot.)
Party officials estimate the March 5 caucus will cost about $500,000, and require 400 work hours on the day of the event. While Paul's campaign is optimistic that the Kentucky GOP central committee will approve the change in plans, lingering concerns remain among state Republican officials about the cost of holding an expensive, time-intensive caucus with such short notice. And the decision comes at at time when Paul is sinking in the polls, overshadowed by Republicans like Donald Trump and struggling to break through the presidential pack.
"People are very much supportive of seeing Sen. Paul further his efforts to become president. The stark reality becomes do we have the money to pay for it?" said Republican Robert Stivers, the president of the state Senate. "It has been more of a money concern than anything else."
In a last-minute effort to alleviate such concerns, Paul's campaign took the extraordinary step of pledging to pay most of the costs out-of-pocket. Earlier this week, his campaign deposited $250,000 into a state party account, but the Lexington Herald-Leader reported Tuesday the funds had not yet been deposited.
"I will fully fund this caucus," Paul wrote. "I want to make sure NO COUNTY CHAIR or (the Republican Party of Kentucky) will be on the hook for ANY money for this caucus."
The rest of the required funds, Paul proposed, would be raised by charging other campaigns that choose to participate in the caucus through a $15,000 per candidate access fee.
On the ground in Kentucky, Paul's team has also engaged in a statewide lobbying effort to convince central committee members to support the plan by assuring them it won't cost the state party.
"They're really trying hard," Adair County Republican Chairman Shannon Rowe told CNN. "They're being pretty aggressive."
Later this week, Paul—who is currently in Haiti providing pro-bono eye surgery as part of a summer mission trip—will host a conference call with voting committee members to provide more details for his funding plan, his campaign told CNN.
When the state party's executive committee first proposed the plan earlier this spring, Paul's presidential campaign was soaring. The junior senator was heralded in Time magazine as "the most interesting man in politics," and he was in the top tier of presidential polls. But over the past few months, the emergence of other candidates—particularly real estate mogul Donald Trump—combined with Paul's fundraising struggles and the indictment of the campaign's close allies on conspiracy charges stemming back to Paul's father's 2008 presidential run, Rand Paul has struggled to regain his footing.
The effort began as a way to pave the way for what appeared to be a sure-to-be competitive native son in the spring, but Paul's decline in the polls has left some voting members less enthusiastic about the move.
"I think a lot of folks suspected they'd be a bit tighter," Scott Lasley, a Kentucky GOP official, told CNN.
The latest CNN/ORC presidential poll
puts Paul in the middle of the pack with just 6% support among registered Republican voters nationally.
Talk of Paul's success as a reason for holding the caucus "has not come up as frequently," Lasley said. "That's gone from about 80 percent of the people I've talked to from about ten person of people who bring that up now."
Regardless of Paul's chances, party officials also see it as an opportunity to make Kentucky more relevant in the presidential process. As a state that traditionally holds its election in late spring—a time when White House primaries are often no longer competitive—candidates largely ignore the state or don't see it as a campaign priority. But moving the contest to early March could finally make the Bluegrass State a player in presidential politics.
"We're ignored. It has been pretty boring in presidential races," Lasley said. "The most attractive part for a lot of folks is whether or not this will attract attention to Kentucky and make us relevant in the Republican nomination process."