Tea party lawmakers will keep up the pressure on Boehner. Some said the election of Scalise, a conservative from Louisiana, would not be enough to meet their demands for greater representation in leadership.
With the risk of possible challenges to leadership in a fresh vote after the November elections, Boehner, McCarthy and Scalise will have to work hard to keep their conservative wing satisfied if they want to remain in their jobs.
The new leadership team immediately faces a series of upcoming legislative deadlines, including replenishment of the Highway Trust Fund, which will run out of money for new highway construction projects by late August.
House Republicans have ruled out an increase in federal fuel taxes but have failed to agree on other ways to find the $19 billion needed to pay for highway projects over the next year. Proposals have included savings from ending Saturday U.S. mail deliveries and revenue gained by allowing companies to repatriate profits at a lower tax rate.
Democrats have proposed closing some corporate tax breaks to raise highway funds, a move that has been resisted by both moderate and conservative Republicans. If a deal cannot be reached, delays for new projects could start by August and all federal highway funding could stop by Sept. 30
Congress also must resolve disputes over annual spending bills needed to keep government agencies open past the Sept. 30 fiscal year-end. Republican House-passed versions of some of these measures contain significant cuts to transportation grants and housing subsidies, which Senate Democrats want to reverse.
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A further tilt to the right would be "palpable" next year if Republicans win control of the Senate and increase their House majority, said Rep. John Fleming, a Louisiana conservative. Another extension of the federal debt limit that is needed by March 31 would require cuts to benefit programs such as Medicare and Social Security, he said.
"We're going to be sending the president legislation and putting it on his desk for signature that has the kind of reforms the American people demand," Fleming said.
Immigration reform legislation is all but dead in the House. Tea party candidate David Brat defeated Cantor, in part by attacking him for his openness to legal status for some children brought to the United States illegally by their parents. Brat's upset victory is likely to further spook Republicans who might be inclined to support immigration reform.
Rep. Chris Van Hollen, the top Democrat on the House Budget Committee, said he believed the Republican leadership reshuffle would add up to less compromise.
"I fear that the situation in the House has grown even more difficult because the signal that was sent to the House Republican caucus by Congressman Eric Cantor's defeat was, 'Don't even whisper about compromise on these big national issues,'" Van Hollen said.