WATCH: Tim Kaine Makes Campaign Trail Debut: 'I Like To Fight For Right'

Appearing on stage together for the first time since Friday's vice presidential announcement, Hillary Clinton and Tim Kaine made a push for voters of color by highlighting his record on diversity and civil rights.

Kaine also spoke about gun violence, job creation, equal pay and raising equal pay — all mainstays of Clinton's campaign.

Clinton said Kaine has "lived" the values of diversity. That, she argued, is in contrast the GOP ticket and last week's Republican National Convention. "Tim Kaine is everything Donald Trump and Mike Pence are not," she said.

She also used a line she has used to describe herself in an attempt to appease Sanders and other progressive supporters who feel Clinton — and now Kaine — are too moderate. "When I say he's a progressive who likes to get things done, I mean it."

Acknowledging that many voters may not know his record or even his name, Kaine ticked through his bio as a civil rights lawyer and public office.

"I like to fight for right," he said.

Kaine also talked about gun violence and serving as governor during the 2007 mass shooting at Virginia Tech. Choking up, he said that day was the "worst day of my life."

He peppered his speech with Spanish, and a little Spanglish:

"Benievenidos a todos en nuestro pais, verdad, porque somos Americans todos," he said. ("Welcome to all in our country, right, because we're all Americans.")

"We're going to be compañeros de alma (soul mates) in this great lucha (fight) ahead," he said.

But Kaine mostly used his time to enthustically endorse Clinton and draw sharp contrasts with Donald Trump. Calling her the "opposite" of Trump, he said "Hillary Clinton doesn't insult people, she listens to them. What a novel concept."

Kaine ended with a call-and-response with the audience.

"Do you want a 'you're fired president or a 'you're hired' president?" Kaine asked. "Do you want a 'me first' president or a 'kids and families first' president?"

Sanders supporters struggle to get on board

Clinton and Kaine will be officially nominated this week at the Democratic National Convention in Philadelphia.

Ahead of its start Monday, some Bernie Sanders supporters there expressed reservations about Kaine's record and worry that he's not progressive enough.

Referring to Kaine as "more conservative than Hillary Clinton," Sanders supporter Cameron Sato of Honolulu told NPR that "by picking someone who's that progressive ... they're not necessarily pushing the agenda in the way we want to see it."

"I would have campaigned for Hillary Clinton, I would have busted my butt ... if she had picked Elizabeth Warren," he said.

"It makes me wonder, is she really going to follow through with all those progressive platforms and things she's claiming she's going to get passed through?" pondered Asami Kobayashi also of Honolulu.

Both said Clinton's choice of Tim Kaine make it harder to vote for her.

However, Ben Jealous, former head of the NAACP feels that Kaine can be pivotal in helping Clinton win over African American and Latino voters.

Jealous favors Bernie Sanders — and is at the convention pushing to eliminate superdelegates — but says Clinton's "pick has is made" and that he'll support the ticket.

The key to getting minority voters on board, he said, is playing to Kaine's strengths as a former civil rights leader, mayor of a black city and his ability to speak Spanish. That record, he says, will give the party an opening to "invest in turning out black and brown vote."

But it's up to Democrats to use that record to their advantage, he says. "In order for Tim Kaine's pick to be as valuable as it can be," he continued, "that's what her campaign, that's what the DNC that's what our party needs to be investing in right now."

"And, by the way, we need to do that to beat Donald Trump," Jealous said.

If Saturday's event is any indication, the Clinton campaign knows how vital that is, too.

Asma Khalid contributed to this report.

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