And for all the attention paid to Obamacare, Republicans betray concern that Sink's persistent attacks linking Jolly to efforts to privatize Social Security are paying dividends.
The NRCC attacked Sink recently when she made a vaguely positive reference to a bipartisan 2010 deficit-cutting blueprint that proposed gradually raising the Social Security retirement age and slowing the growth in benefits, while also cutting Medicare.
Sink, who did not endorse the plan in her initial remarks, said in a statement: "I am opposed to any changes that would raise the retirement age, reduce the guaranteed Social Security benefit or privatize Social Security in any way."
The slice of Florida that is ground zero in the battle over Obamacare is anything but representative of America. In addition to the presence of tens of thousands of retirees, relatively few blacks or Hispanics live in the district and median income is several thousand dollars below the national average.
That combination might ordinarily tilt the district Republican. Yet while Young carried it with ease, Sink won it in a losing campaign for governor in 2010, and Obama carried it narrowly in 2008 and 2012.
Early voting by mail points to a close race. Throughout this past week, about 63,000 ballots had been returned, slightly more by Republicans than Democrats, with about 15 percent of the total cast by independents.
Nor is it clear what will motivate voters to side with one or the other contender.
Buddie Berger, 93, and a resident of The Palms of Largo, says she's for Sink because "Social Security should not be privatized."
Helen Eden, an even 100, says with a smile she is "not necessarily" going to vote the same way. A Mitt Romney supporter in 2012, she says she is worried about "mainly the budget and our president and how he is bankrupting our country."
The U.S. Chamber of Commerce, the Republican Congressional Committee and Jolly have invoked Obamacare in television commercials. "Cancelled health plans, higher premiums, Medicare cuts, people losing their doctors, a disaster for families and seniors," says the announcer in the Chamber of Commerce ad.
In one of his own campaign's ads, Jolly says, "I'm fighting to repeal Obamacare right away."
Private polling in both parties says that while the health care law is unpopular, outright repeal is trumped by a rebuttal like Sink's — that parts must be fixed, but simply eliminating it would empower the insurance industry.
In another ad, Jolly says, "Let's replace Obamacare," a position that is broadened on his campaign website. It says Obamacare "should be repealed now, and then Congress and the administration should begin to consider private sector solutions that address very specific problems in the health insurance industry."