A simmering clash between Gov. Tim Walz and Republican lawmakers over a two-year budget deal boiled over on Saturday as GOP senators began contingency plans for a government shutdown while Walz rallied his base.

The negotiators returned Sunday to continue talking.

After days of relative silence, Walz gave a spirited, campaign-style speech in the Capitol rotunda Saturday to his oldest political allies — the state teachers union, which has been pressing for more school spending. As he spoke, partisan warfare ignited anew in the Senate, where the GOP majority passed a lean, stopgap spending measure that Republicans said could head off a potential government shutdown.

The 35-31 party-line vote laid down a marker as talks resumed Saturday night in an effort to break the budget impasse before the Legislature is scheduled to adjourn on Monday. The GOP plan would keep the government running if leaders fail to negotiate a state budget by July 1.

Moments after the vote, Senate Republicans gathered on the Capitol steps, each holding pieces of paper signifying public services such as parks and fishing licenses that could be hampered by a government shutdown.

"It's extremely important that we keep Minnesota open," said Sen. Karin Housley, R-St. Marys Point, touching off "Keep Minnesota Open" chants from her colleagues.

Democrats called the GOP move a charade to bypass serious budget talks and avoid compromise.

"We see this Washington-style politics on the national news every day and we haven't done that here in Minnesota," said Senate DFL Leader Tom Bakk, DFL-Cook. "It's our job to put together a responsible two-year budget that addresses the needs of our citizens and our state."

The contrasting scenes reflected the strains of more than a week of closed-door budget talks that had broken off at 12:45 a.m. Saturday. Until Saturday afternoon, each side had largely maintained a careful silence on the status of the talks, suggesting that they were at a sensitive juncture and didn't want to jeopardize a deal.

But Walz's speech, combined with the GOP gambit in the Senate, suggested that the two sides might be retreating to their corners, increasing the likelihood of a special session or even a government shutdown.

Walz, a former high school geography teacher and football coach before serving in Congress, told hundreds of teachers inside the Capitol rotunda that voters sent him and the Legislature to support education, which Democrats say would suffer under the GOP budget proposal.

"When Minnesotans spoke last year," he said, referring to the 2018 election results that made him governor, "They told us very clearly, invest in our schools, invest in the teachers that make it happen and invest in our children."

The Senate's "lights on" bill would keep state government running if no deal is reached before the current budget expires June 30. Senate Republicans on Saturday called the measure a responsible "insurance policy" to stave off what would be the state's first government shutdown since 2011.

"Our political reality is what it is and we cannot deny that," said Sen. Roger Chamberlain, R-Lino Lakes, the bill's lead sponsor. "We should always prepare for the worst."

But the gesture is meaningless unless the DFL-controlled House follows suit, which seemed unlikely. Instead, DFL lawmakers slammed the funding bill as a stunt that would relieve pressure on Republicans in budget negotiations, saying it would shortchange Walz's promises to boost state funding on priorities such as health care, education, roads and security in the state's prisons.

'Throwing the towel in'

In a fiery floor speech, Bakk hit the Republicans' measure as "throwing the towel in on negotiations." Chamberlain described the bill as a prudent measure to avoid teacher layoffs and keep parks and government offices open — including those that license bars and alcoholic beverages.

"The beer will keep flowing with no interruption in delivery," he said.

As talks resumed Saturday night, Walz, Senate GOP Leader Paul Gazelka and House DFL lawmakers were still trying to bridge key differences over spending and taxes in the nation's only divided legislature. The two-year state budget is expected to top $45 billion.

To pay for better schools, roads and health care, Walz and the House DFL want to raise the gas tax and keep in place a tax on health care that would otherwise expire this year. Republicans say Minnesotans' taxes are already too high.

The Senate's temporary spending bill tracks closely with the GOP's initial budget proposal, with none of the tax hikes sought by Walz and House Democrats to pay for their new spending initiatives. It would also let Republicans blame Democrats, if they reject the extension, for any resulting government shutdown.

"You know, maybe this was the plan all along: that we would spend no more money than we spent last time," Bakk said.

Lawmakers in conference committees working to reconcile different parts of any final budget agreement were still waiting Saturday for budget targets needed to complete their legislation.

In his most extensive public remarks on the closed-door budget talks, Walz offered a sharp rebuke to Republican lawmakers. "What I don't recall them saying," he said, referring to the voters, "is negotiate away our future to give tax breaks to millionaires."

In a nod to his strong backing from the teachers union, Education Minnesota, Walz said he always wondered who got to sit at the table where final budget negotiations take place. "Guess what? 80,000 teachers sat at that table" this year, he said, referring to the union's membership.

The crowd's booming cheers echoed throughout the Capitol.

Walz and his entourage hustled away from the rally and back into his office to continue strategizing what increasingly looks like a stalemate with Republicans.