WASHINGTON » Twenty months into a Congress they have tilted rightward, tea party loyalists are finding that ideological purity can be elusive for conservative lawmakers trying to balance their convictions against constituents’ election-year needs.

Rep. Paul Ryan, who has won tea party praise as Mitt Romney’s vice presidential pick, had a General Motors assembly plant that was about to be shuttered in his hometown of Janesville, Wis., when he voted for the $14 billion auto industry bailout in 2008. The seven-term House Republican also voted for the $700 billion financial industry rescue that same year.

He has since criticized both efforts by President George W. Bush to combat that year’s near economic collapse. Yet his votes — plus his support for Bush’s 2003 debt-financed expansion of Medicare to provide prescription drug coverage — rankle conservatives to this day and underscore the challenge of adhering to small-government principles when voters’ bread-and-butter interests are at stake.

More recently, this campaign season has seen some of the House’s most conservative members split over a sweeping farm bill, disaster aid to drought-battered farmers and legislation to finance transportation projects and keep student loan interest rates from ballooning. Such divisions have dampened the expectations of tea party leaders, with some now saying it will take several elections before they win the Washington clout they need.

"No one is going to agree with us 100 percent of the time," Jenny Beth Martin, a national coordinator for the Tea Party Patriots, said of members of Congress. "And we do understand they do have to look at what’s best for their district and their constituents."

Martin said that most of all, tea party supporters want lawmakers to be firm in their convictions. Out of 240 House Republicans and 47 GOP senators, she said there are fewer than 30 House members and about five senators she can reliably count on for support, with too many others focused on bringing federal largesse back home.

"We just don’t have very many visionary people stepping up in our political landscape right now at all," Martin said.

The struggles conservatives face were illustrated just before Congress recessed for August, when the House approved $383 million in agriculture disaster aid, mostly for livestock producers and tree farmers.

Conservatives ended up on both sides of the 223-197 vote. One of the "yes" votes came from Rep. Tim Huelskamp, R-Kan., who has one of the House’s most conservative voting records and whose district has one of the nation’s heaviest concentrations of farms.

Huelskamp said he has repeatedly told constituents that they will be affected by efforts to curb federal deficits, including reductions in farm support. A farmer himself, Huelskamp said he voted for the disaster aid because it was paid for by cutting conservation programs.

"I thought it was fiscally responsible," he said.

That wasn’t the view of Rep. Jim Jordan, R-Ohio, a House conservative leader who opposed the bill. He said he wants less federal involvement in the private sector and complained that the savings to pay for the measure’s one year of disaster aid was being culled from conservation programs for a decade into the future.

"The first principle is what’s good for your country is good for your constituents," Jordan said. "And what’s good for your country is not to spend money you don’t have."

Divisions like that among conservatives have not been unusual.

The conservative Club for Growth, which advocates lower taxes and less regulation, scores lawmakers’ voting records based on bills it considers key.

Of the 46 House Republicans the club considered the most conservative, 27 voted for the disaster aid bill, 17 voted against and two did not vote. On the bill approved in June on transportation and student loans, 28 voted against, 16 voted for and two were absent.

"The reality is most members of Congress look to see what gets them re-elected and that drives their ideology more than a detached view of policy," said Chris Chocola, the club’s president and a former House member.

Conservatives showed their clout last month when they prevented House GOP leaders from bringing a massive bill renewing agriculture programs to a vote in the chamber, arguing that its farm subsidies and food stamps were too costly.

Yet even that bill highlighted internal divisions. Four of the most conservative members, as measured by the Club for Growth, had voted for the bill when it was approved by the House Agriculture Committee, while two voted against it.

Tea party-backed Rep. Marlin Stutzman, R-Ind., opposed the broad bill at the Agriculture Committee, calling it too expensive. He backed the disaster measure on the House floor, arguing that it merely provided money the government committed to in a farm bill four years ago.

"With a drought across the country, there are priorities. As conservatives we set our priorities what is important and what is not, and I felt that was part of an obligation," Stutzman said of the disaster aid.

As for Ryan’s 2008 votes, he said then that the financial industry bailout would preserve the free enterprise system. On the auto industry rescue, he said his district’s economic hardships had been "downright gut-wrenching." Now chairman of the House Budget Committee, Ryan has since criticized both measures, saying the Obama administration misused them.

Matt Kibbe, president of FreedomWorks, which often works with tea party groups, said the organization likes Ryan’s willingness to propose conservative budgets but has not forgotten his votes on the bailouts and the Medicare prescription drug expansion.

"We’ve had our disappointments and arguments with Paul over the years," said Kibbe. "He’s definitely not perfect. But in presidential politics, there’s no such thing as perfect."