WASHINGTON — As he began his first re-election run in early 2013, tea party Rep. Thomas Massie had no trouble raising money from business interests.
Then came 2015.
The Kentucky Republican voted against returning John Boehner, R-Ohio, to the speaker's job and opposed an effort by GOP leaders to avoid a standoff with President Barack Obama over immigration that threatened to shut down the Department of Homeland Security.
In the first three months of 2013, Massie reported $46,000 rolling in from tobacco, trucking, health care and other industries. During the first quarter of 2015, Massie has collected just $1,000 from political action committees, which funnel contributions to candidates from business, labor or ideological interests. That money came from the conservative Eagle Forum.
Massie and some other conservatives say the reason their business contributions have fallen is simple: GOP leaders are retaliating for their defiance.
"Those who don't go along to get along aren't going to get as many PAC checks," Massie said last week, using the acronym for political action committees.
None offers concrete proof that top Republicans are behind the contribution falloff. But they say the evidence is clear.
"I'm an engineer with a science background. I look at empirical evidence. If you have enough data points, you can prove something," Massie said.
Conservatives point out that leadership has targeted them before, and they cite Boehner's removal of some rebels from coveted committee assignments. In March, an outside group allied with GOP leaders ran radio and Internet ads accusing some House Republicans who opposed efforts to end the Homeland Security impasse of being "willing to put our security at risk."
GOP leaders deny they have orchestrated an effort to deny business support to recalcitrant conservatives, arguing that they want to protect Republican-held seats. But they acknowledge that votes can have consequences with business groups whose political spending plays major roles in congressional campaigns.
"If they agree with what the speaker is trying to accomplish and you don't support the speaker, why should they support you?" asked Rep. Tom Cole, R-Okla., a Boehner ally.
Reports filed with the Federal Election Commission show that many GOP rebels are having a harder time raising cash from corporate interests, while others are not.
In a public show of disloyalty that party leaders scorn, 25 House Republicans voted against Boehner to be speaker last January, including one who voted "present." Of the 24 expected to seek re-election next year, 15 saw their contributions from PACs fall between this year's opening quarter and the same period in 2013.
For a few who did not file reports for the first quarter of 2013, this year's data was compared with the earliest report from their 2014 campaign.
None of the 24 has received contributions yet this year from political committees run by Boehner and the other two top GOP leaders, Majority Leader Kevin McCarthy of California and Majority Whip Steve Scalise of Louisiana, according to FEC reports. The three leaders have donated to dozens of other House Republicans, chiefly those facing tight re-elections.
All except perhaps three of the 24 mutinous Republicans are in safe GOP districts and should breeze to re-election.
In the first quarter of 2015, maverick Tim Huelskamp of Kansas saw his contributions from political committees fall in half from the $35,000 he reported raising during that period in 2013. He says lobbyists have told him of a "do not give list" from top Republicans that names about 35 GOP lawmakers.
"Folks understood, 'Hey, you may not get what you want if you're helping the folks'" on the list, said Huelskamp.
Leading Republicans deny such a list exists.
"That is beyond conspiracy theory, because if someone was going to do the list, it would be me," said Rep. Devin Nunes, R-Calif., a Boehner friend and frequent critic of his party's insurgents.
Top Republicans say campaign contributions can vary over time for several reasons, including a preference by many donors to help incumbents in tight races or freshmen as well as lawmakers' own money-raising efforts. They note that the first quarter of a nonelection year is early, with plenty of time for donations before the November 2016 election.
"You can blame failure on a lot of fathers," said Rep. Greg Walden, R-Ore., who leads the National Republican Congressional Committee, the House GOP campaign organization.
Not all rebellious Republicans whose business contributions have dropped blame party leaders, and many have found ways to offset the smaller amounts they've raised from political committees.
Of the 24 House Republicans who opposed Boehner's re-election, half have raised more this year than they did in early 2013 and 18 have fatter campaign treasuries than they did then.
Rep. Daniel Webster, R-Fla., got 12 votes for speaker in January. His political committee contributions plummeted from $38,000 in the first quarter of 2013 to $3,000 this year.
But thanks to a huge jump in individuals' donations, Webster raised $233,000 overall from January through March of 2015, nearly $100,000 more than in early 2013. He says he's not aware of GOP leaders steering business money away from him.
"I would suspect if people like the job I'm doing, they're going to give to us," he said.