Even before Hillary Clinton chose him as her vice presidential running mate, Virginia Sen. Tim Kaine was on TV, explaining how he had been completely open about gifts and free travel he had accepted between 2006 and 2010 as the state's governor.

"The key was disclosure," he said on MSNBC, "and nobody's ever raised a concern that anybody who contributed, whether a campaign contributor or a gift giver, ever got anything for it."

Kaine was referring to more than $160,000 in gifts and trips – from basketball tickets to a trip to the Caribbean — which he accepted as governor-elect and governor. All of it was properly reported under state disclosure laws, but in this election, when liberals and conservatives alike are declaring "the system is rigged," disclosure may no longer be the key.

For Democrats, here's the problem: They have treated this as a question of complying with Virginia's famously weak disclosure laws, which Kaine did. But a ferocious contest for the White House is no place for polite debate. The issue will likely be dealt with in political attacks — and ads.

"I would use this to further the narrative that politicians like Hillary Clinton cannot be trusted," said Jeff Berkowitz, CEO of Delve, a conservative opposition-research firm. "If she is put into the White House with Tim Kaine, they're going to work for the special interests and not the American people."

Such a tactic is made easier by voters' rejection of old-style politics this year. It also cuts against the nice-guy, neighborly dad image that has so far been the image presented of Kaine.

An unknown quantity open to being defined

Kaine enters the national political spotlight almost as an unknown, and Republicans are racing to define him. Video of his MSNBC interview was posted on YouTube by America Rising, a Republican opposition-research group.

Donald Trump dismissed Kaine in typical Trumpian language on Fox News: "I mean gifts and trips and clothing and all sorts of things. And now he's running for vice president? I don't get what's going on here. He was not a good choice for her."

Also on Fox, former New York City mayor Rudy Giuliani compared Kaine to his successor as governor, Republican Bob McDonnell. "All the same stuff that happened to McDonnell," Giuliani said, "and McDonnell got prosecuted and he's sittin' there, free and — just like Hillary." Giuliani chuckled twice.

The comparison to McDonnell is an important argument for Republicans. He was prosecuted after taking even more than Kaine — $175,000 in loans and gifts, including an engraved Rolex watch, designer clothes for his wife and golf gear — from a single benefactor: a businessman who wanted McDonnell's help in marketing a dietary supplement.

The difference here was that McDonnell didn't disclose all of his gifts. A jury convicted McDonnell on 11 corruption charges, a verdict overturned this summer by the Supreme Court.

Democrats reject the comparison. Kaine told MSNBC he did nothing wrong. "I reported everything I was given, even if I didn't keep [it]," he said. "I didn't keep the vast majority of it."

What did he get and what could it mean?

Most of what Kaine disclosed was free travel: an $18,000 stay at the Caribbean estate of a friend; $45,000 in campaign travel, reimbursed by the Obama presidential campaign; and trips to policy conferences on the private jets of corporations seeking his attention.

In one case, Kaine disclosed a $12,000 flight to Aspen for a meeting of the Democratic Governors Association, a trip aboard a jet belonging to Barr Pharmaceuticals, on which he was accompanied by a Barr lobbyist. The trip was reported by the New York Times, as were a flight and Final Four basketball tickets from Dominion Virginia Power, and other favors from companies that wanted some sort of gubernatorial boost.

That attitude also encourages advocates of stronger campaign finance laws.

"You know, you gotta kind of wonder what the people who were vetting Kaine for the Clinton campaign were thinking when they stumbled across this stuff," said Nick Penniman, director of the group Issue One, which is trying to build a bipartisan reform coalition.

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