When she defeated Sen. Bernie Sanders to lock up the Democratic presidential nomination, Hillary Clinton promised outreach to his liberal supporters. Though she moved to the left on key issues and granted concessions on the party's convention platform, progressives eyed a bigger prize: Sanders, or someone like him, selected as Clinton's vice president.

Instead, late Friday Clinton picked Tim Kaine, a genial, veteran senator from a must-have swing state who fills a lot of her strategic and political needs. A former Virginia governor with foreign policy experience, Kaine has deep ties to President Barack Obama, who hand-picked him to run for the Senate, and is highly popular in his home state.

"I'm thrilled to tell you this first: I've chosen Sen. Tim Kaine as my running mate. Welcome him to our team," Clinton posted on Twitter late Friday.

I'm thrilled to announce my running mate, @TimKaine, a man who's devoted his life to fighting for others. -H pic.twitter.com/lTVyfztE5Z — Hillary Clinton (@HillaryClinton) July 23, 2016

"Tim is a lifelong fighter for progressive causes and one of the most qualified vice presidential candidates in our nation's history," Clinton said in a separate statement.

“The Democratic ticket now features two environmental champions, both of whom understand that Americans want our government to secure a clean energy future for our kids and grandchildren," Kevin Curtis, executive director of the NRDC Action Fund, said in a statement Friday. "Sen. Kaine’s impressive environmental record is a perfect match for a presidential candidate who puts so much emphasis on creating green jobs and expanding America’s reliance on clean, renewable energy. We applaud this choice and will work hard to help the Clinton-Kaine campaign win in November.”

But as a moderate, free-trade Democrat with no enmity towards Wall Street -- or any other obvious, left-wing bona fides -- Kaine also checks a lot of boxes on the Bernie-or-Bust grievance list. And die-hard Sanders supporters haven't been shy about saying so.

"Let's be really clear: It should be disqualifying for any potential Democratic vice presidential candidate to be part of a lobbyist-driven effort to help banks dodge consumer protection standards and regulations designed to prevent banks from destroying our economy," Charles Chamberlain, executive director of Democracy for America, a liberal advocacy group, said in a statement issued Thursday

There's no doubt Kaine is highly qualified for the job, with plenty of governing experience.

He broke into politics as a Richmond city councilman in the mid-1990s, ascended to mayor not long afterward and was elected Virginia's lieutenant governor in 2002. He won the governor's office in 2006, serving one four-year term; he was one of the first elected officials to endorse then-Sen. Barack Obama when he announced his presidential bid in 2008.

Obama tapped Kaine to head the Democratic National Committee in 2009, then urged Kaine -- who left the governor's mansion with high public approval ratings -- to run for the open seat vacated by former Virginia Sen. Jim Webb, a Democrat who retired in 2012. A reluctant candidate, Kaine nonetheless defeated George Allen, the former Republican governor and one-time senator, by 6 points in the general election.

Analysts say Kaine will bring a lot to the Clinton ticket: deep legislative experience, an ability to relate to white men in the Rust Belt as well as minorities and exurban soccer moms, and he has Senate friends on both sides of the aisle. He's also got a compelling personal backstory, growing up in a blue-collar Minnesota family, then serving as a Catholic missionary in Central America before settling in Richmond and entering politics.

"You can see he's from Virginia, which has been a key swing state in the last two presidential elections, and the outcome in Virginia most closely matched the national outcome," says Geoffrey Skelley, a political analyst at the University of Virginia's Center for Politics.

The choice also plays into the campaign's electoral strategy, Skelley says: deny Republican nominee Donald Trump a swing state he'll absolutely need to win the White House. "I think the attitude of the Clinton campaign is if maybe they can lock up Virginia, it reduces the number of paths Trump has" to the presidency, he says.

Kaine is fluent in Spanish, which can help Clinton broaden her appeal to Latino voters, who have all but lined up around the block to vote against Trump. But as an electrifying show dog who can light up a campaign stage, or an attack dog who'll snarl at Trump -- traditional roles of a vice presidential candidate -- Kaine, by his own definition, is far less likely to bark or bite.

"I love that about him," Clinton told CBS News' Charlie Rose in an interview earlier this week when asked if he was too vanilla for Clinton's ticket.

In this nasty election cycle, that's a plus, says Skelley.

.@timkaine is as decent, honorable, selfless soul as you will ever meet. A man with the heart of a servant, who is "woke". @HillaryClinton — Jennifer Granholm (@JenGranholm) July 23, 2016

"He's definitely the antithesis of what this election has been -- very ugly, very negative," Skelley says. "His natural inclination is relatively positive, even when he's being critical. He just doesn't come across as being negative."

That hasn't stopped his critics, particularly those on the left, from grumbling about his place on the ticket.

Liberals point to his support for global trade deals, including his vote to give Obama "fast-track" authority for the Trans-Pacific Partnership, a sweeping trade deal the president loves and progressives consider a non-starter. Kaine was one of 70 senators who signed a letter asking the Consumer Financial Protection Bureau to adjust financial rules covering community banks and credit unions, which progressives consider a love letter to Wall Street.

"That sentiment flies in the face of the majority of Democratic voters who supported both Clinton and Senator Bernie Sanders," Maine state Rep. Diane Russell, a progressive Democrat, said in a statement.

Stephanie Taylor, head of the Progressive Change Campaign Committee, said in a statement Friday that picking Kaine leaves Clinton vulnerable.

"As we saw in Donald Trump’s speech last night, Republicans will run hard against Democrats on trade this year. Unfortunately, since Tim Kaine voted to fast track the Trans-Pacific Partnership, Republicans now have a new opening to attack Democrats on this economic populist issue," Taylor said. "It’s now more important than ever that Hillary Clinton run an aggressive campaign on core economic ideas like expanding Social Security, debt-free college, Wall Street reform, and yes, stopping the TPP. It’s the best way to unite the Democratic Party, and stop Republicans from winning over swing voters on bread-and-butter issues."

"Clinton should push the White House to take TPP off the table in a lame-duck Congress in order to avoid this vice presidential pick allowing Donald Trump to outflank her on this key issue," Taylor added.

On Friday afternoon, a hashtag of dissent, #NotKaine, was trending on Twitter.



"The Bernie Sanders people are not going to be happy with the Kaine pick," Skelley says. But Clinton's reasoning, he says, is that Kaine will do more good than harm, and "her calculation is that Kaine widens her appeal to a group of voters who maybe are a little more skeptical of her," including "disenchanted independents."

"She decided that the left will come home enough that it won't be a problem," he said.

As expected, Republican National Committee Chairman Reince Priebus also was not impressed with Clinton's pick, and telegraphed the GOP's anticipated line of attack.

“Hillary Clinton’s choice of Tim Kaine does nothing to unify a fractured Democrat base which is repelled by her dishonesty and cronyism,” Priebus said in a statement late Friday. “After spending last week pandering to grass-roots Democrats with Bernie Sanders, Hillary Clinton has chosen someone who holds positions that she’s spent the entire primary trying to get to the left of."

But Katrina vanden Heuvel, editor of The Nation, a liberal newsmagazine, said progressives need to get a grip and focus on the big picture. There's more to Kaine than meets the eye, she said -- including his record as a blue governor of a then-red state -- and he can in fact help Clinton win the White House.

Kaine, she writes in a Huffington Post blog entry, "is pretty liberal for a Virginian. During the [gubernatorial] campaign, he was derided relentlessly by the GOP, in an expensive and vicious campaign, as 'the most liberal candidate who’s ever run for governor in the Commonwealth of Virginia’s history.'"

Clinton's choice for veep, she adds, "is a guy who made a name for himself working with the American Civil Liberties Union, who connected his faith to his politics in authentic ways (he was a thoughtful opponent of the death penalty), who was an honest and forthright advocate of government’s affirmative role—supporting moves to increase taxes to fund education, transportation and environmental programs."

Skelley concurs: "He's been sort of portrayed as really, really moderate, and I don't know if that's really accurate."

"I do feel like if Kaine is the pick, there will be some moments where the Clinton campaign will use him as a surrogate" to Latino voters, says Skelley. "He's given a speech in Spanish on the Senate floor -- he's fully capable of doing that. I can see him in the veep debate dropping a line in Spanish."

Ultimately, Clinton apparently wanted a safe pick, and "I think the fact that he may be comfortable in the No. 2 role can be a positive for him," Skelley says. Nevertheless, he adds, "vice presidential picks can add a little bit of an edge to their home state -- it can be anywhere from 1 to 3 points. He makes a leaning-Clinton state maybe even likely-Clinton."

And while progressives aren't going to be happy, Kaine does have some liberal causes in his background, including representing minorities in housing discrimination as a Harvard-trained lawyer working in Richmond.