When Sen. Jeff Sessions, one of Congress's most hard-line immigration lawmakers, became the first sitting U.S. senator to endorse Donald Trump in February, many of his Senate colleagues scoffed. The prevailing sentiment among Capitol Hill Republicans was that Trump wasn't one of them.

Now that Trump is the presumptive Republican presidential nominee, many Republican lawmakers still don't think Trump represents them or the party. But given Trump's improbable rise to the top, it's time they reconsider, Sessions said in a recent interview with Glenn Thrush's "Off Message" podcast for Politico.

"My advice is to listen and accept the will of the American people, the Republican voters — the Republican Party is the Republican voters," Sessions told Thrush. "Give me a break! A lot of our drift within our party has gotten away from [the will of the voters]."

In other words, Trump and his supporters aren't the ones out of step with the party. The Trump haters are.

And Sessions is probably right about that — at least, when it comes to this new, populist shade of the Republican Party that Trump appears to be leading.

Let's remember the extraordinary feat Trump accomplished between June, when he got into the race, and now: He's the guy whom millions of Republican primary voters — from nearly every region of the country — liked enough to want him to be their president. He won 20 or so states convincingly. He did what few thought he could and won a majority of delegates to clinch the nomination.

Among Republican diehards, Trump is their man. (How he does among a larger electorate is still something we're gaming out.)

So Sessions has a point when he tells Thrush that Republicans like Speaker Paul D. Ryan (R-Wis.) who hesitate to back Trump are missing the point of why Trump got nominated in the first place: He's promising to take the party in a direction Republican voters like.

"I think [Ryan] needs to recognize, on some of these issues," Sessions said, that "Trump is where the Republicans are and if you’re going to be a Republican leader, you should be supportive of that."

On Tuesday, none other than the Senate majority leader, Mitch McConnell (R-Ky.), reinforced Sessions's argument when he said he doesn't "have any problem supporting" Trump.

But here's where reluctant Trump supporters like McConnell differ with actual Trump supporters like Sessions: "I don't believe Donald Trump is going to change the Republican Party in a fundamental way," McConnell said on MSNC's "Morning Joe."

Sessions thinks Trump already has.

And building a wall and picking fights with the media and musing about temporarily banning Muslims and alienating Hispanics, women and millennials might not be where Republican leaders want to go. But as Sessions predicts to Thrush, they may not have a choice.

"I think the leaders in all parties tend to adjust to reality," Sessions said. "They just have to or they won’t remain in office. … Already many are sensing it.”