In the battle for control of the Democratic party, progressives are increasingly confident they are winning. That’s how they explain the record sums of Super Pac money targeting their candidates in nominating contests for safely Democratic seats.

“There’s a set of people who are uncomfortable with a new brand of politics,” said Maurice Mitchell, national director of the progressive Working Families party. “They’re trying to set the clock back. But the genie’s outta the bottle.”

So far this election cycle, progressives have a mixed record. But a stronger-than-expected showing in last week’s primaries has energized the movement and set the stage, they hope, for even more success this summer.

In Pennsylvania, state representative Summer Lee overcame a deluge of outside spending to win her congressional primary. Lee was declared the winner after three days of counting. She tweeted: “$4.5 mill” with a fire and trash can emoji.

Oregon progressives cheered the victory of Andrea Salinas, who also went up against a crush of big money in one of the most expensive House Democratic primaries in the country. Meanwhile, the seven-term Oregon congressman Kurt Schrader, whose conservative politics drew the left’s ire, appears to be on the verge of losing his seat to progressive challenger Jamie McLeod-Skinner, though results have been delayed by a ballot-printing problem.

And in what will be one of the cycle’s most competitive Senate races, John Fetterman, Pennsylvania’s iconoclastic, liberal lieutenant governor, beat Congressman Conor Lamb, a rising star of the center-left.

The next test of progressive political power comes on Tuesday, in a Texas runoff election between Congressman Henry Cueller, a conservative Democrat backed by party leadership, and Jessica Cisneros, a progressive immigration lawyer endorsed by Alexandria Ocasio-Cortez and Bernie Sanders. And after that, there are competitive intra-party primaries in Illinois, New York and Michigan.

“We’re not doing any victory laps,” Mitchell said. “If anything, those losses and the wins have redoubled our commitment and focus.”

Moderates see the cycle very differently.

They point to a trio of House races last week in North Carolina and Kentucky where the more moderate candidate won handily. Those victories came just two weeks after the Democratic congresswoman Shontel Brown won a fiercely contested rematch in Ohio against Nina Turner, a progressive activist who worked on Sanders’ presidential campaigns.

“People who are far outside the mainstream of the Democratic conference make it harder for moderates to run in swing districts because their ideas and their rhetoric are used against people like Abigail Spanberger,” said Matt Bennett, a co-founder of the center-left thinktank Third Way, referring to the Virginia congresswoman who singled out progressives for costing the party seats in 2020.

Bennett said it was important to distinguish between progressives. He argued that candidates who are “liberal but not radical”, such as McLeod-Skinner in Oregon, pose little risk to swing-state Democrats.

Instead, “we are worried about the Squad”, Bennett said, the group of progressive congresswomen that includes Ocasio-Cortez, “because the people in that wing of the party do not regard it as part of their duty as Democrats to help ensure that we have majorities”.

It’s a charge that angers progressives. Following Sanders’ lead in 2020, they united behind Biden to oust Donald Trump in 2020 and then spent the past year and a half working with congressional leaders and the White House to pass the president’s economic agenda. And yet progressives are the ones being pummeled by outside spending.

A number of contentious Democratic contests have been shaped by Super Pacs, like the one formed by the American Israel Public Affairs Committee, known as Aipac, another supported by the LinkedIn co-founder Reid Hoffman, and another backed by a crypto-billionaire.

Much – though not all – of the outside money has been spent in support of moderate candidates, including in Texas, where Cuellar, the nine-term congressman, is in the fight of his political life.

“This is a David-and-Goliath sort of battle,” Mitchell said.

The rash of spending has only exacerbated tensions between the party’s ideological factions. In a sign of progressives’ building resentment, Jeff Weaver, Sanders’ former campaign manager, warned that progressives could launch third-party candidates in swing districts to scuttle centrist Democrats’ chances.

The suggestion infuriated Bennett, who called it the “most irresponsible thing I’ve seen a Democrat say … maybe ever, particularly in the face of a Republican party that has lost its ever-loving mind.”

Though still early in the primary season, progressives appear poised to expand their numbers in Congress. Still, not every closely fought intra-party battle has fallen neatly along ideological lines.

Oregon’s Schrader, a former leader of the conservative Blue Dog coalition, angered Democrats in the state after his vote against a provision that would allow Medicare to negotiate the price of prescription drugs. Local Democratic leaders voted to endorse his challenger, McLeod-Skinner, sharply breaking with tradition.

In Texas, however, the battle lines are clearly drawn.

Pundits there think the south Texas runoff between Cuellar and Cisneros will prove to be a bellwether of the Democratic mood in a political landscape that increasingly favors Republicans. Democrats have razor-thin majorities in Congress, and the party in power historically loses in the president’s first midterm election.

Democrats are also struggling to outrun Biden’s low approval ratings, weighed down by inflation and widespread frustration with Washington.

Since Cisneros forced Cuellar into a runoff earlier this year, the race has been reshaped by a draft supreme court opinion indicating the justices are prepared to overturn a constitutional right to an abortion.

Cuellar is one of the only Democrats left in Congress who is against abortion. Cisneros, by contrast, has cast herself as a defender of reproductive rights in a state that has effectively banned abortion.

They have also clashed on immigration. Whereas Cuellar staunchly criticizes the Biden administration’s immigration policies, appearing frequently on Fox News to air his grievances with the president’s handling of the border, Cisneros has advocated for a more progressive stance in that sector.

No matter what happens on Tuesday in Texas, progressives believe they have made progress elevating candidates they say will excite the party’s base in November.

In Kentucky, long a Republican stronghold, Democrats nominated Charles Booker, an unabashedly progressive ex-state lawmaker who would be the state’s first black senator. It’s a shift from two years ago, when he surprised the party establishment by nearly defeating its chosen candidate in the Senate primary that cycle.

Booker now faces an uphill battle to unseat the entrenched Republican senator Rand Paul. But he says his progressive Kentucky New Deal agenda is popular with voters of both parties. It’s the partisan labels and political culture wars that get in the way.

“The truth of the matter is, the people of Kentucky want real progress,” Booker said. “It’s just that no one listens to us.

“The policies that I lift up, the issues that I fight for, they’re not radical and they don’t come from some national consultant. This comes from my lived experience of living the struggle that most Kentuckians know well.”