GOP strategists suggest Paul's attacks are part of a strategy to weaken Clinton, one of the few national figures capable of helping embattled Democrats in red states survive the 2014 midterms.
The biggest beneficiary of the attacks on Clinton may be in Paul's own home state, where his GOP colleague, Senate Minority Leader Mitch McConnell, faces a tough re-election challenge from Democrat Alison Lundergan Grimes, Kentucky's secretary of state.
Clinton, a Grimes fundraiser and old family friend, is scheduled to stump for her in Louisville on Feb. 25 -- the 42nd president's first campaign appearance of the 2014 cycle.
Paul can be expected to play a key role for McConnell's campaign during that visit, making the case to voters that Clinton -- and Grimes, by association -- are fatally flawed. A Tea Party favorite and popular in his state, Paul is perhaps McConnell's most influential surrogate.
Grimes has adopted the Democratic message that Republicans are engaged in a "war on women" as a central part of her strategy to win over female voters and oust McConnell. Paul's spotlight on Clinton's past sexual foibles could undermine that effort.
"Clinton was relatively popular here so we need someone to go and remind people just how terrible of a person he was," said a Republican operative with Kentucky ties. "Paul has the sort of celebrity status to do that effectively, and I think people are glad he is."
The Democratic Party remains strong in Kentucky at the state and local levels. But races for president and Senate have belonged to the GOP since Clinton won a three-way race for the Bluegrass State in 1996 with 46 percent of the vote. In 2012, President Obama lost Kentucky to Republican nominee Mitt Romney by nearly 23 points, winning only four of the state's 120 counties.
GOP strategists see Paul's attacks helping beyond Kentucky. Republicans need a net of six seats to take the Senate, and their path to the majority runs straight through a handful of conservative-leaning states that are currently held by Democrats.
In states like Arkansas and Louisiana, where Democratic incumbents are running for re-election, President Obama is too toxic to provide any assistance, while Bill Clinton is viewed as an asset to woo soft partisans and swing voters.
Paul has slammed Clinton repeatedly as a "sexual predator" for his 1998 affair with then-White House intern Monica Lewinsky, dredging up the former president's past missteps.
The controversy over Clinton first surfaced last September in a Vogue magazine interview with Paul and his wife Kelley. In the interview, Kelley Paul described Clinton's affair with Lewinsky as "predatory" and "offensive to women."
During an interview in January on NBC's "Meet The Press," Paul defended his wife's remarks.
"He [Clinton] took advantage of a girl that was 20 years old and an intern in his office...There is no excuse for that, and that is predatory behavior," said Paul. "Someone who takes advantage of a young girl in their office? I mean, really. And then they have the gall to stand up and say, 'Republicans are having a war on women?'"
Paul told the Washington Examiner on Thursday that there was no "grand strategy" behind his criticism of Bill Clinton.
But the senator didn't try to distance himself from the comment, signaling instead that he would continue raising Clinton's past infidelity in the months ahead.
"People keep asking me about Bill Clinton, so I just tell them my opinion," Paul said.
Paul also said Clinton was overestimating his ability to help Grimes in her race.
"I think he mistakes his popularity in Kentucky ... I think Kentuckians don't really relate to him -- or his behavior, really," said the senator.
Paul is personally invested in McConnell's re-election. He backed the incumbent while many of the Washington, D.C.-based conservative groups who championed Paul's outsider campaign in 2010 have coalesced behind McConnell's primary opponent, Matt Bevin.
Paul though is also eyeing a presidential bid and Republicans familiar with his thinking acknowledge there is an element of 2016 maneuvering in his attacks on Clinton. Polls show Clinton's wife, former Secretary of State Hillary Clinton, as the Democrats' clear frontrunner.
The Republican base still despises the former president and his wife, and GOP operatives say it is shrewd of Paul to attack them. Doing so helps expand his profile as a national Republican leader and can boost his fundraising.
But while most pundits see Paul's attacks as 2016 posturing, many insist Paul's strategy is primarily about gaining an edge for Republicans in the 2014 midterms, undercutting Clinton's ability to help Democrats hold the Senate.
Clinton's personal history is an embarrassing counter to Democratic charges of a Republican "war on women." Democrats are hoping to survive a tough midterm election for their party by pushing women away from the GOP, which has hemorrhaged support among female voters in recent elections.
Republican strategists worried that female voters could abandon the party in the midterms are pleased to see Paul hitting back.
"What he's doing could be really clever," said a Republican operative.