Some progressives and former backers of Bernie Sanders' presidential candidacy started signaling their dissatisfaction with the choice of Sen. Tim Kaine as Hillary Clinton's running mate before it was even announced on Friday night.
Already suspicious of Clinton's commitment to liberal policies, they were closely watching her decision on the vice presidency, wary for any sign that she may be drifting back to the political center as she prepares for the general election.
Choosing Kaine would be "greeted by many as confirmation that she intends to run away from, if not betray, the progressive base of the party," said Benjamin Jealous, a prominent Sanders supporter and former president of the NAACP.
Their concerns with Kaine have focused on economic issues. The Virginia senator supported legislation in the Senate that was key to advancing the massive 12-nation Trans Pacific Partnership trade agreement, which is a priority of the Obama administration but opposed by both Sanders and Clinton.
And then this week, liberal groups targeted Kaine for signing two letters to the Obama administration seeking modifications to banking regulations that would benefit smaller and community banks.
Democracy for America described the changes sought by Kaine and other senators as a "lobbyist-driven effort to help banks dodge consumer protection standards and regulations designed to prevent banks from destroying our economy."
"Making Sen. Tim Kaine our vice presidential candidate could be potentially disastrous for our efforts to defeat Donald Trump," the group said.
The vice presidential selection alone would not threaten party unity heading into the convention and the fall, a person within Democracy for America said, noting a concern for Democrats as they work to bring Sanders' backers into the fold after a long primary. They are anxious to avoid depressing enthusiasm with key activists, which could hurt fundraising and voter turnout efforts.
"It's coming from a place of deep concern," the group official said. "We need to desperately need to defeat Donald Trump and we want to make sure the base of the party is as fired up about doing so as they possibly can be."
Adam Green, founder of the Progressive Change Campaign Committee, which was neutral in the primary but has ties to Massachusetts Sen. Elizabeth Warren, questioned the choice of a running mate who supports the TPP.
"It will be very ironic if voters go into election day thinking Donald Trump is better on the TPP issues than the Democratic Party," he said.
Green had championed Warren as a possible running mate for Clinton.
"There is a difference between a checklist liberal and a bold progressive. Elizabeth Warren has been at the high-water mark of what changing the entire national conversation looks like," he said.
Supporters of Kaine have pointed to other parts of his record, such as his successful push for strengthening background checks for gun purchases after the shooting massacre at Virginia Tech in 2007. He also has a perfect voting record from leading abortion-rights groups despite considering himself personally antiabortion because of his Catholic faith.