What’s up with the family business is a perennial default conversation starter at so many Thanksgiving dinners. And that’s likely to be especially true around the tables of families in the business of winning federal campaigns.

From the three-years-away handicapping of the next presidential race to the premature speculation about who might fill a possible opening in the House, a big share of campaign talk these days is once again about American political dynasties — their virtues and flaws, staying powers and limitations, rising stars and fading forces.

There are plenty of clans, of course, that produce generation after generation of attorneys, retailers, farmers, physicians and funeral directors. And there are plenty of other countries where, for varied cultural and economic reasons, a disproportionate share of the power is reposed under just a couple of surnames. (Typhoon recovery in the Philippines, for example, is being made more complex these days by the three-decade feud between the rival Aquino and Romualdez families.)

But few perceptions about the political elite in the United States appear to generate as much public attention — and annoyance — as the belief that the top jobs are too much the province of a chosen few, in direct contrast to our meritocratic and democratic ideals. That notion is reinforced by the fact that at least one person named Bush or Clinton was a candidate in eight straight national elections until 2012, and may well be once again in 2016.

Membership in Congress isn’t as dynastic, much as it sometimes appears that way. There’s a pair of brothers (the Levins), a set of sisters (the Sanchezes) and a team of first cousins (the Udalls). Beyond that, just four senators (both Udalls among them) and 18 House members (4 percent of the total) have a parent who served in Congress.

The parentage is almost evenly split between the parties; all those forebears were fathers, and all are gone from the Capitol now. But with congressional approval ratings at their nadir and anti-incumbent sentiment on the rise, the suspicion lingers that too many seats in Congress are passed down along with so many other family heirlooms, even though only nine current members were their fathers’ immediate successors.

The talk about dynastic endurance was only heightened by last week’s saturation coverage of the 50th anniversary of the death of President John F. Kennedy, the highest-achieving member of what’s undeniably the most storied clan in Democratic politics. His father had been a prominent ambassador, and his grandfather was Boston’s congressman. At the front of JFK’s funeral cortege were his brothers: the attorney general (and later a New York senator) and the Massachusetts senator, each of whom had a son who spent more than a decade in the House.

Now, one of Robert F. Kennedy’s grandchildren, Joseph P. Kennedy III, is a freshman Massachusetts congressman — and the first member of a fifth generation to serve at the federal level. And the fevered gabbing has already started about how JFK’s only grandson, Jack Schlossberg, who was much in evidence at last week’s commemorations, sounds ready to join his second cousin in the arena as soon as practical.

As he’s only a 20-year-old undergraduate at Yale, that moment’s sure to come after a handful of other families figure out whether to make their next moves.

The more immediate decisions are confronting a pair of Republicans in southwestern Florida. Connie Mack IV and Chauncey P. Goss II have unexpectedly been presented with a potential opening to restore their families’ winning congressional records, thanks to last week’s cocaine possession guilty plea by freshman Rep. Trey Radel.

While the 37-year-old Radel spends the rest of the year in rehab, presumably assessing his political future, Mack and Goss will be weighing their prospects — regardless of whether the incumbent runs in the Aug. 26 primary, which is tantamount to the general election in the solidly Republican Gulf Coast district. Other local players are contemplating the same, but none has much of a political pedigree.

Goss, a Beltway consultant who came within 6,300 votes of besting Radel in the 2012 primary, is the son of Porter Goss, who held the House seat for 16 years before leaving for a short stint running the CIA. Mack, who held the seat for eight years before his unsuccessful Senate bid two years ago, is not only the son of a two-term Florida senator, but also the great-grandson and great-great grandson of Texas congressmen. (He was also half of the third-ever married couple of House, although he and California’s Mary Bono, who lost in 2012, are now divorcing.)

And what of the dynastic expansions at the national level?

Hillary Rodham Clinton hasn’t committed to stopping the ceaseless speculating for as long as another year, but every indication is that she’ll declare sooner rather than later that she wants to become the first former first lady returned to the White House as her own woman.

And just last week, Jeb Bush touted his credentials as a “practicing” conservative to a high-profile audience in New York and left no doubt he would be considering a presidential bid.

“I have not gotten advice, and I have not sought it yet,” the former Florida governor said, although he’s keenly aware that his brother, the previous president, really wants him to run while his mother, the former first lady, really doesn’t. “There’s a time to make a decision, and you shouldn’t make it too early.”

Electing “Bush 45” would mark the first time three people from the same family have been president — besting the record shared by the Adams father and son, the Harrsion grandfather and grandson and the Roosevelt fifth cousins.

Candidacies by Connie, Chauncey, Hillary, Jeb — and someday young Jack — would inevitably face all sorts of challenges. A threshold question, though, is this: Would they be punished beyond recovery, or rewarded beyond justification, simply for trying to apply their own brand to the family firm?