“I wish they all fit that hard-line, anti-spending stereotype, but sadly they are not,” Darling said.

Sarah Binder, a congressional expert at the center-left Brookings Institute think tank in Washington, said Boehner and House Majority Whip Kevin McCarthy of California had to spend a lot of time “educating” many tea party freshmen on the realities of governing.

“Boehner and McCarthy had to work really hard to convince some of the freshmen that shutting down the government was not a strategy they should take seriously,” Binder said. “And during the debt-ceiling crisis in the summer of 2011, they had to bring in outside experts to convince them that default was not an option.”

Most of the 1,552 House votes in the current legislative session have been on uncontroversial issues with broad bipartisan support, such as measures naming post offices and other public buildings or resolutions honoring constituents’ significant achievements.

But some of the 150 or so important votes not only divided Democrats and Republicans, but also split Republicans.

“I don’t think [Republican] party loyalty runs as deep with some members of the freshman class as it does generally,” Mulvaney said in a recent interview. Mulvaney is among the 10 tea party newcomers who’ve voted against Boehner more than 10 percent of the time. Among his high-profile votes were those refusing to raise the national debt ceiling, a tea party point of view that drew national attention in summer 2011.

A May 9, 2012, vote on $40 billion in additional government subsidies for U.S. exports split the tea party freshman contingent almost exactly in half, with 32 backing the increased Export-Import Bank loans and 36 opposing them. That vote pitted Republicans’ traditional support for business against their aversion to government interference in the free market.

The next day, 16 Republican lawmakers, including four first-termers, broke ranks and joined Democrats in voting against a bill to replace $1.2 trillion in forced cuts — a process known as sequestration — scheduled to start in January. The bill would have spared military cuts by replacing them with other funding hits.

“One of the areas I’ve had frustration within my party is a real refusal to find waste and abuse in the Pentagon budget,” said Rep. Jaime Herrera Beutler of Washington state, one of the four tea party newcomers who opposed the measure.

The analysis of key votes reveals a libertarian wing within the tea party freshman class. While they share other Republicans’ dislike of federal spending, the libertarians are more wary than their peers of expanding the government’s non-fiscal powers.

On Dec. 14, 2011, 18 first-termers voted against a $640 billion defense authorization bill that the House passed with broad bipartisan support because of an anti-terror clause giving the government new powers to arrest and detain Americans without charge. Amash, whose views often align with the libertarian policies of 2012 GOP presidential candidate Ron Paul, branded the measure “one of the most anti-liberty pieces of legislation of our lifetime.”

These examples don’t, however, reflect a wave of anti-establishment thought among tea party freshmen. Almost all members of Congress, Democrats and Republicans alike, vote how their party leaders tell them to vote nearly all the time. In the current legislative session that began in January 2011, the 435 House representatives have followed their party leaders’ positions 92.3 percent of the time.

For the 68 tea party freshmen, the figure is exactly the same — 92.3 percent of their votes have hewed GOP party lines.

That similarity is a bit deceptive, though: New lawmakers historically are more conformist than veterans, so the two groups matching each other in the current term suggests an uptick in independent thinking for the tea party freshmen of the 112th Congress.

Mulvaney said he and other tea party lawmakers ran for Congress because Republican leaders pursued big-government policies such as the No Child Left Behind education mandates, Medicaid coverage of prescription drugs and the 2002 McCain-Feingold campaign finance law.

“I got into it because I didn’t like what the Republican Party was doing,” Mulvaney said.