President Trump begins his second 100 days with major campaign promises held hostage by a stubborn Republican Congress even as GOP voters show faith in his leadership.

The repeal of Obamacare was on life support after legislation pushed by the White House was shelved Friday for a second time in weeks amid Republican opposition in the House. The logjam denied the president a key legislative victory in his first 100 days.

The prospects for tax reform were equally uncertain after Republicans two days earlier announced opposition to critical elements of Trump's blueprint. The president was even denied money for construction of a wall along the Southern border in a must-pass spending bill.

The roadblocks have materialized because Republicans in Congress feel empowered to assert independence from Trump on issues of disagreement. That's despite the president receiving high job approval ratings from the Republican voters who elected him.

"It's obvious that there's a lot more undercurrents and undertows and crosscurrents here than maybe the administration originally anticipated," Rep. Peter Roskam, R-Ill., said in an interview with the Washington Examiner. "My first responsibility is to reflect my constituency."

Trump presided over the confirmation of a Supreme Court justice he nominated, signed executive orders to unwind regulations implemented by former President Barack Obama and signed bills undoing laws enacted by his predecessor, putting the little-used Congressional Review Act to effective use.

But the president's goals for reforming healthcare, taxes and immigration, and for rebuilding infrastructure could have a permanent, lasting impact on the country long after his presidency. And, they are either stalled amid Republican infighting or have yet to take flight.

That's because Trump has surprisingly little political influence with conservatives. They represent districts that strongly supported the president in 2016, but bucked him anyway when the original version of the Obamacare repeal bill, the American Health Care Act, was proposed.

Conservatives chose principles over Trump, an admirable quality but revealing of how little juice the president has with anti-establishment members who should constitute his base of support in Washington.

It's been frustrating for Trump's allies on Capitol Hill. "Congress needs to do a better job in understanding the reason Donald Trump is our president," Rep. Mike Kelly, R-Pa., said. "My request of my colleagues is, all the time, you keep pushing back against him. Why?"

Now, Trump is being whipsawed my centrist Republicans, who are rejecting changes made to the AHCA to satisfy conservatives. The change weakened protections for Americans with pre-existing medical conditions in a bid to reduce insurance premiums, the No. 1 goal of conservatives.

The episode doesn't bode well for tax reform. Centrists could be sensitive to Democratic attacks that Trump's tax plan is a giveaway to the wealthy at the expense of the middle class. Conservatives might balk at projections that it would blow up the deficit. The proposal calls for reducing taxes on corporations and small businesses by 20 percent.

Rep. Chris Collins, R-N.Y., another chief Trump ally, conceded that the president's unpopularity outside of Republican circles is damaging his political influence with centrists on healthcare. Many are running for re-election in traditionally GOP districts that sided with Hillary Clinton or were competitive.

"There's no question that a number of folks in the Tuesday Group — Clinton won their districts — and those districts by and large would be in favor of Obamacare," Collins said.

Trump's inexperience is part of the problem. Neither he nor members of his senior team tasked with negotiating big legislative deals have ever done so before.

White House strategy, say multiple Republican insiders with ties to Capitol Hill, has been virtually nonexistent when it comes to addressing the parochial concerns of individual members and satisfying the philosophical and political priorities of the various factions.

It's probably cost the president some wins in his first 100 days, and he's going to have to adjust and improve his negotiating skills in this arena if he doesn't want to repeat outcome over the next 100 days.

"They're playing checkers, not chess," a former House Republican aide said, on condition of anonymity in order to speak candidly. "The administration is thinking linear not strategically."

Trump concluded his first 100 days in office historically unpopular for a president at this stage. His job approval rating in the RealClearPolitics average was just 43.1 percent, with 51.9 percent disapproving.

Among Republicans, however, Trump is in good shape.

The president rated an 85 percent in CNN's latest poll. And, in a poll conducted for the University of Virginia Center for Politics, self-identified "Trump supporters" who pulled the lever for him in November scored him a 93 percent.

These voters are pleased with the progress he's making on fulfilling his commitments and believed he's accomplished a lot so far. The White House has promoted Trump's first 100 days achievements as historic and unprecedented.

"I think we've done more than perhaps any president in the first 100 days," Trump said on day 97, in an interview with the Examiner.