BOSTON — The Republican Party seems as divided and angry as ever.

Infighting has penetrated the highest levels of the House Republican leadership. Long-standing geographic tensions have increased, pitting endangered Northeastern Republicans against their colleagues from other parts of the country. Enraged tea party leaders are threatening to knock off dozens of Republicans who supported a measure that raised taxes on the nation’s highest earners.

“People are mad. ... I’m right there with them,” Amy Kremer, chairman of the Tea Party Express, said late last week, declaring that she has “no confidence” in the party her members typically support.

Her remarks came after Republican lawmakers agreed to higher taxes but no broad spending cuts as part of a deal to avert the “fiscal cliff.”

“Anybody that voted ‘yes’ in the House should be concerned” about primary challenges in 2014, she said.

At the same time, one of the Republican Party’s most popular voices, New Jersey Gov. Chris Christie, blasted his party’s “toxic internal politics” after House Republicans initially declined to approve disaster relief for victims of Hurricane Sandy. He said it was “disgusting to watch” their actions and he faulted the party’s most powerful elected official, House Speaker John Boehner, R-Ohio.

The Republican Party’s internal struggles to figure out what it wants to be were painfully exposed after Mitt Romney’s loss to President Barack Obama on Nov. 6, but they have exploded in recent days. The fallout could extend well beyond the party’s ability to win policy battles on Capitol Hill. It could hamper Republicans as they examine how to regroup and attract new voters after a disheartening election season.

To a greater degree than the Democrats, the Republican Party has struggled with internal divisions for the past few years. But these latest clashes have seemed especially public and vicious.

“It’s disappointing to see infighting in the party,” said Ryan Williams, a Republican operative and former Romney aide. “It doesn’t make us look like we’re in a position to challenge the president and hold him accountable to the promises he made.”

What’s largely causing the dissension? A lack of a clear Republican leader with a single vision for the party.

Republicans haven’t had a standard-bearer since President George W. Bush left office in 2008 with the nation on the edge of a financial collapse. The rise to a tea-party movement infused the Republicans’ conservative base with energy. The tea party is credited with broad Republican gains in the 2010 congressional elections, but it’s also blamed for the rising tension between the pragmatic and ideological wings of the party — discord that festers still.

It was much the same for Democrats in the late 1980s, before Bill Clinton emerged to win the White House and shift his party to the political center.

2012 presidential nominee Romney never fully captured the hearts of his party’s most passionate voters. But his tenure atop the party was short-lived. Since Election Day, he has disappeared from the political world.

Those Republican leaders who remain engaged — Christie, Boehner, Senate Minority Leader Mitch McConnell of Kentucky and Republican National Committee Chairman Reince Priebus — are showing little sign of coming together.

Those on the Republican Party’s deep bench of potential 2016 presidential contenders, including Florida Sen. Marco Rubio, Wisconsin Rep. Paul Ryan and Louisiana Gov. Bobby Jindal, have begun staking out their own, sometimes conflicting, ideas for the party.

Obama has outlined a second-term agenda focused on immigration and gun control; those are issues that would test Republican solidarity even in good times. Deep splits already exist between Republican pragmatists and the conservative base, who oppose any restrictions on guns or allowances for illegal immigrants.

With Boehner unable to control his fractured caucus, the White House is left wondering how to deal with the House on any divisive issue.

Fiscal issues aren’t going away. The federal government reached its borrowing limit last week, so Congress has about two or three months to raise the debt ceiling or risk a default on federal debt. Massive defense and domestic spending cuts are set to take effect in late February. By late March, the current spending plan will end, raising the possibility of a government shutdown.

Frustrated conservative activists and Republican insiders hope that the continued focus on fiscal matters will help unite the factions as the party pushes for deep spending cuts. That fight also may highlight Democratic divisions because the party’s liberal wing vehemently opposes any changes to Social Security or Medicare

“Whenever you lose the White House, the party’s going to have ups and downs,” Republican strategist Ron Kaufman said. “My guess is when the spending issues come up again, the Democrats’ warts will start to show as well.”