A “lightweight,” an “idiot” and a “beggar” were just a few of the go-to epithets Donald Trump hurled at Sen. Lindsey Graham last week, before giving out the senator’s cellphone number to the world.

But there’s at least one way in which the billionaire businessman holds his Republican presidential rival in high regard: Graham is the most recent person to receive one of Trump’s campaign contributions.

The $2,600 check was written in October, just before the senator was re-elected in South Carolina and seven months before either announced a bid for the White House and started their public feud. The donation is yet another reminder of the unusual, and sometimes, awkward transformation Trump is making from behind-the-scenes political financier to omnipresent force as a candidate.

It’s been widely reported that, during the years when his attention was focused on luxury real estate development, Trump was an ideological inconsistent who flirted with third-party movements as well as both parties — while donating the majority of his political money to Democrats. He says that made complete business sense because the party wielded most of the power in New York and other places he had big investments.

But a decided shift in his giving strategy, especially at the national level, began a decade ago and solidified in 2008, when he first considered running for the GOP presidential nomination. Of the $746,000 he’s donated since 2005 to federal candidates and political committees, 80 percent has gone to Republicans, according to the OpenSecrets.org database.

Some of those donations look unusual at best — and out-of-place at worst — in light of Trump’s current circumstances.

The Graham gift is only the most recent example. Before launching his presidential bid, Trump donated to super PACs of two current rivals: An organization benefiting former Gov. Mike Huckabee of Arkansas received $2,500 in 2012, and the group created to help Sen. Ted Cruz of Texas got $5,000 in 2014. (Trump has done nothing to help the other GOP senators running against him now, Rand Paul of Kentucky and Marco Rubio of Florida, and he donated $4,800 to Rubio’s principal senatorial rival five years ago, then-Gov. Charlie Crist.)

A decade ago, however, Trump was a generous contributor to re-election races by the governors of both states where he splits his time, George Pataki of New York and Jeb Bush of Florida, both of whom are now with him in the presidential field.

And Trump’s criticism of John McCain’s war record, which has become the biggest dust-up of his nascent campaign, makes all the more surprising his gift of $4,600 to the Arizona senator’s 2008 presidential campaign (the maximum “hard-money” donation allowed that year.) He stayed totally out of the last presidential race, even as his namesake son donated a combined $36,000 to Mitt Romney and the Republican National Committee.

But for someone running to be the GOP’s choice in 2016, the most uncomfortable thing he’s done with his checkbook is making seven donations totaling $10,200 to Hillary Rodham Clinton. Almost half the money was proffered when she was not only his home-state senator, but also a candidate for the presidency in 2008. New York’s current senators, by contrast, have received significantly less; Trump has given Kirsten Gillibrand $6,400 and her fellow Democrat Charles E. Schumer $4,000.

(Trump hasn’t donated to a Democrat in almost three years; the last was Kathy Hochul, now New York’s lieutenant governor, who got $1,200 for her unsuccessful bid to hold an upstate House seat in 2012.)

When it comes to Congress, Trump’s long-standing practice has been to focus his donations on members who represent places where he has houses or does business, and people in the leadership. What has changed was his shift toward the GOP, which curiously began soon after he put $53,000 behind the Democrats’ successful effort to take over the Capitol in 2006. He invested $83,000 in the GOP’s campaign to win back Congress in 2010, then donated $100,000 to Speaker John A. Boehner’s leadership PAC, along with $62,000 to the National Republican Senatorial Committee in 2012.

He was way more generous in the last cycle, pouring $107,000 into the three main GOP campaign committees, giving $60,000 to Senate Majority Leader Mitch McConnell’s leadership PAC, writing $2,000 checks to six candidates who are now freshman senators and being comparably generous to almost two dozen winning House candidates, many from the party’s tea party wing.

Rep. Steve King of Iowa, the state of the first caucuses, shares Trump’s anti-immigration platform and has been the biggest GOP beneficiary of the billionaire’s largess in recent years, reaping $6,600 since 2012.

The member with the biggest haul in the past two decades is Democratic Rep. Charles B. Rangel of Manhattan, the heart of the Trump Organization empire, who received $11,500 — but has not gotten a dime since ethics problems prompted his loss of the Ways and Means gavel in 2008.

Close behind are Mark Foley, who represented Trump’s principal residence in Palm Beach, Fla., and received $10,500 before resigning in disgrace in 2006, and Frank A. LoBiondo, who has represented the Trump casinos in Atlantic City, N.J., since 1995 and has received $8,800 along the way.

A central part of the Trump ethos has always been that he knows how to pick a winner, and when it comes to congressional candidates Trump has had a pretty good track record. In the past two decades he’s only donated to a dozen candidates who never got to Capitol Hill, while giving to more than 90 others who were either incumbent members or on the way to winning their seats.

The Donald also has an equally well-publicized abhorrence for losers, and this is also manifest in his campaign finance history. He donated $500 to the 2010 re-election of GOP Rep. Christopher Lee in upstate New York — but got his money back a few months later, as soon as the congressman quit after revelations he’d trolled for female companionship on Craigslist with the help of a shirtless selfie.

Trump was as blunt back then as he is about other congressional beneficiaries who displease him now. “I think he should resign because he’s stupid,” he said of Lee on CNN. “I mean, can you imagine!”

This year, the process of opening his wallet wide to underwrite for his own quest began in March with his only 2015 donations on file with the Federal Election Commission — $5,000 checks to the state Republican parties of New Hampshire and South Carolina, the sites of the first two primaries next year.