For the better part of a year now, Republicans have tried and largely failed to define Joe Biden — or even just to make people dislike him. And with his 100th day as president approaching, they’re admitting as much.

The Hill’s Jordain Carney spoke with a number of GOP senators who either tacitly or explicitly acknowledged their inability to set a tone in opposing Biden. Sen. Mike Braun (Ind.) said the GOP was doing “poorly” on this front. The No. 2-ranking Senate Republican, Sen. John Thune (S.D.), said, “We need to get better at it.” But “it’s probably harder to attack somebody who is relatable and likable,” he added. The party’s former No. 2 senator, John Cornyn (Tex.), agreed that “it’s always harder to fight against a nice person.”

There is a certain amount of hand-wringing and “Republicans in disarray!” involved in all of this. It’s still early in the Biden presidency. As many of these same GOP senators noted, presidents at this stage of their first term often benefit from something of a honeymoon period, in which people give them the benefit of the doubt.

Biden also undoubtedly benefits from the contrast he has set up with the chaotic presidency of Donald Trump, simply by conducting himself in a relatively normal fashion. But that also could have a shelf life.

All of that said, it’s worth evaluating just how much Republicans have failed in their efforts to knock Biden down a peg and where he stands at this point in his presidency relative to others.

The standard measure is one’s approval rating. It stands at a pretty steady average of 53.3 percent in the FiveThirtyEight average of polls, compared with 40.6 percent disapproval — a net of plus-13 points.

That’s better than at any juncture of Trump’s presidency, which never peaked above majority support and was in net-positive territory (i.e., more people approving than disapproving) for only his first 10 days or so in office.

But relative to other past presidents, Biden’s numbers don’t compare nearly so favorably. At this stage in Barack Obama’s and George W. Bush’s presidencies, they were each at 62 percent approval, according to Gallup data. Bill Clinton was at 55 percent. George H.W. Bush was at 58 percent. Ronald Reagan was at 67 percent.

Against that backdrop, it’s much easier to dismiss Biden’s early popularity as just the normal course of things — a honeymoon Trump never really got but that has been reinstated for his successor.

At the same time, we are in a more polarized era than 12 years ago or three decades ago, in which it’s often difficult for any politician to get even majority approval. If Biden could somehow maintain this — which is a big if and which we’ll return to later — it would certainly buck the historical trend.

Perhaps an even better comparison when it comes to how Biden is doing — and the GOP’s inability to define him — might be perceptions of him on the key issues of the day. Many things color an overall approval rating, including polarization and personal feelings, but views of policies and performances on specific issues can provide insight into how lasting such popularity might be.

And this might be an area in which the GOP hand-wringing is most warranted. Biden is actually doing better than his overall approval rating when it comes to things such as the coronavirus, the covid relief bill he signed and his infrastructure and jobs package. His average approval rating on the coronavirus is 62 percent. The $1.9 trillion coronavirus relief package often polled even better, with some surveys putting support for it as high as the 70s. And early polling on his nascent infrastructure and jobs bill last week showed support at 64 percent in one poll and 56 percent in another. A third poll showed that all of the key elements of it have majority support, with several at 60 percent or more.

The one issue on which Biden is struggling is the border; polls show his handling of unaccompanied minors is underwater. A Quinnipiac University poll last week showed just 29 percent of respondents approved of Biden’s handling of the border, which Biden labeled a “crisis” this weekend, while 55 percent disapproved. The situation notably threatens to loom over much of the early part of Biden’s presidency, although it doesn’t yet appear to be front-of-mind for voters in evaluating him.

Biden’s performance on his early legislative initiatives, though, provides an interesting comparison to his predecessors.

Obama also forged a stimulus bill in his early days — in response to the financial crisis — but that was much more polarizing. Unlike Biden, Obama was actually more popular personally than his stimulus package, which upon passage generally had the support of a slight majority. That stimulus bill also gradually became less popular over time in a way we haven’t yet seen for Biden’s relief package. Obama’s numbers on the economy more broadly were also declining faster by this point than we’re seeing with Biden and the preeminent issue today: the coronavirus.

Bush didn’t come into office with such immediate and divisive problems — apart from the contested 2000 election — but his first major legislative win was in passing tax cuts in May 2001. Polls showed then that those tax cuts were modestly popular, but they were usually around 50 percent approval. Interestingly, at the time, Bush was also often more popular than his signature legislative effort.

Clinton’s biggest early initiative was on balancing the budget, for which he used tax increases and spending cuts. But as the package was being debated, it often polled poorly, and he suddenly found himself as the most unpopular new president since World War II.

As Clinton showed, these early reviews are just that: early. Four years is a long time for a president to either sink or rise, and early popularity often fades rather quickly. In addition, as Republicans do and will remind you, much of Biden’s early legislative push involves spending money on popular programs. Messaging against that is more difficult.

But as Obama’s experience with his stimulus package showed, that’s not always a ticket to public approval. Republicans in many ways successfully argued that spending was out of control in the early part of Obama’s presidency — with an assist from the bank bailout that actually passed on his predecessor’s watch — and Obama’s party paid the price in the 2010 midterms.

We thus far haven’t seen anywhere near a cohesive or effective message against Biden’s coronavirus stimulus or infrastructure and jobs bills, just like we haven’t seen a cohesive or effective message on much of anything from Republicans. The result has been that the coronavirus stimulus has polled as one of the most popular major pieces of legislation in decades, and Biden’s overall handling of the pandemic is a feather in his cap.

The result has also been that much of what Biden is doing is actually more popular than he is personally, which is unusual at this juncture of a presidency this century, even if presidential popularity isn’t. And as those perceptions of his signature legislation and his handling of the biggest issue cement themselves in people’s minds, it becomes more difficult to knock him down personally.

Which might be, even though it’s still early, why we’re seeing the kind of fretting evident among certain Republicans right now.