President Donald Trump laid out a sweeping legislative agenda in his first address before a joint session of Congress, but he faces battle after battle to enact it — many with members of his own party.

The 45th president, addressing lawmakers at the start of just his sixth full week in office, spoke in his familiar brusque and clipped cadence, a stark contrast to the oratory style of his predecessor, Barack Obama, who often mixed professorial lectures with prose that highlighted his self-described “writer’s sensibility.” On the other hand, Trump’s address was chock full of the pithy and blunt phraseology that helped him win the White House.

In the days before his first prime time address as president, senior White House aides and Trump himself repeatedly told reporters the still-new president has been steadily checking off campaign pledges.

“He obviously is in the promise-keeping business,” Senate GOP Whip John Cornyn of Texas said hours before the president made the drive up Pennsylvania Avenue. To that end, Trump wasted little time during the address in ticking off a list of his first-month moves.

“We have begun to drain the swamp of government corruption by imposing a five-year ban on lobbying by executive branch officials — and a lifetime ban on becoming lobbyists for a foreign government,” Trump said. “As promised, I directed the Department of Defense to develop a plan to demolish and destroy ISIS.

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“My administration has answered the pleas of the American people for immigration enforcement and border security,” he said, referring to moves he has made using his executive powers.

Yet, just how he will convince lawmakers to approve of many of his goals failed to come into sharper focus Tuesday night.

For example, when it comes to replacing Obama’s 2010 health law or getting tougher on undocumented immigrants or increasing defense spending at the expense of deep domestic cuts or building a massive wall along the expansive U.S.-Mexican border or a pricey infrastructure enhancement vision, Trump spoke mostly in broad strokes.

He promised that “dying industries will come roaring back to life,” vowed that military veterans will get care, and declared he will see to it that “gleaming” roads, bridges and airports are erected from coast to coast. “We will keep our promises to the American people,” he said.

But if congressional Republicans expected to hear policy details to assuage any concerns about how he will do that and whether they can fall in line behind him, Trump offered few.

He talked about the national debt, the trade deficit and a “series of tragic foreign policy disasters.” Notably, on each matter, he mostly reiterated earlier statements from the campaign or his first month in officer, offering few clues about his planned tactics.

Trump has used his executive authorities to attempt to temporarily ban individuals from seven Muslim-majority countries from entering the United States (which has been frozen by federal courts), kick-start two pipeline projects Obama had blocked, target immigration “sanctuary cities,” and reconsider an Obama-era federal rule on clean water.

But as the pace of those executive actions has slowed, even before he stood behind the podium in the ornate House chamber, Trump is learning that keeping many of his other campaign-trail promises might prove difficult.

That’s because he needs Congress to send him legislation enacting many of his vague proposals — or at least, in many cases, something very similar. And, as the president is finding, when the members of a chief executive’s own party disagree on how to tackle major issues, pursuit of a legislative agenda can come to an abrupt halt — no matter the final Electoral College margin.

There are signs of differences between Trump and factions of his party. Democrats signaled hours before the address in the House chamber that big parts of Trump’s agenda already appear on shaky ground, and the reactions of Trump’s fellow Republicans added weight to such claims.

During the address, GOP members who have been active on immigration, such as Sens. John McCain of Arizona, Lindsey Graham of South Carolina and Jeff Flake of Arizona, remained seated when Trump talked about his intention for “proper vetting” of immigrants.

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Dartmouth College professor Richard Wright said the need for a such a bill “has never been more urgent,” adding current “piecemeal efforts” are too tailored for merely “specific groups of people.” He warned that Trump’s early moves on immigration “will rip families apart, and therefore runs counter to decades of precedent and policy.”

At one point, he urged Republicans and Democrats to send him a bipartisan immigration overhaul bill.

“I believe that real and positive immigration reform is possible, as long as we focus on the following goals: to improve jobs and wages for Americans, to strengthen our nation’s security, and to restore respect for our laws,” he said, laying down his markers. “If we are guided by the well-being of American citizens, then I believe Republicans and Democrats can work together to achieve an outcome that has eluded our country for decades.”

Meanwhile, on health care, House Minority Whip Steny H. Hoyer of Maryland told reporters earlier Tuesday that Republicans, due to divisions within the conference, do not have the votes to repeal the Affordable Care Act.

Perhaps that’s a big reason why Trump, at several points, extended olive branches to Democrats.

“I am calling on all Democrats and Republicans in Congress to work with us to save Americans from this imploding Obamacare disaster,” Trump said, then including several issues Democrats long have supported in his plea for bipartisan cooperation.

“My administration wants to work with members in both parties to make child care accessible and affordable, to help ensure new parents have paid family leave, to invest in women’s health, and to promote clean air and clear water, and to rebuild our military and our infrastructure,” the president said.

Yet, there were signs inside the chamber that when Trump can attract Democratic support, like on an infrastructure package, he likely will lose many Republicans over its price tag.

Republicans were slow to rise when he mentioned it, and House Majority Leader Kevin McCarthy, R-Calif., and House Majority Whip Steve Scalise, R-La., remained in their seats.

Even Trump’s Transportation Secretary, Elaine L. Chao, told governors gathered in Washington on Sunday that deciding how to pay for infrastructure spending would be difficult.

“Everybody wants a better transportation system, but very few people want to pay for it. so that’s a big conundrum. There are a number of pay-fors for improving our very critical infrastructure, and the pay-fors are going to be hard,” Chao said.

“That’s going to be a tremendous challenge,” she said.

The overall vision he laid out on the most divisive issues, such as the 2010 health law, is unlikely to attract many Democratic votes.  After all, he wants to terminate its individual mandate that all Americans be covered.

“Mandating every American to buy government-approved health insurance was never the right solution for America,” Trump said. “The way to make health insurance available to everyone is to lower the cost of health insurance, and that is what we will do.”

But the new leader of the GOP appeared to do little to build bridges among the various factions within the party. Speaker Paul D. Ryan’s office blasted out a statement highlighting Trump’s embrace of tax credits and broader health savings accounts as a sign “the White House and Congress are coalescing around a particular approach,” an aide to the GOP leader wrote in an email.

After all, one sentence in a lengthy speech won’t easily bridge divisions on the issue among Republicans that erupted into public view a day earlier.

Republican Study Committee Chairman Mark Walker and House Freedom Caucus Chairman Mark Meadows on Monday said they cannot support the emerging GOP plan, a signal Ryan might lack the 218 GOP votes to pass such a plan, as Hoyer asserted. Walker and Meadows cited concerns over the plan’s refundable tax credits, saying it amounts to a new entitlement program.

The North Carolina Republicans said Monday that several of their colleagues feel the same way and predicted that the plan could not pass the House in its current form.

No Democrats are expected to join Republicans in voting to repeal the 2010 health care law, so GOP leaders need 218 of their members (out of a current roster of 238 Republicans; soon to be 237 if the Senate confirms Rep. Ryan Zinke as Interior Secretary on Wednesday, as expected) to vote for whatever legislation they produce.

Health care is not the only issue on which the new president appears to be entering choppy waters. Several longtime Washington observers called his coming budget plan dead on arrival — largely because of GOP skepticism about increasing defense spending by $54 billion at the expense of domestic programs that even many Republicans support.

Yet, Trump did little in his address to try to sell his coming spending level proposals to the lawmakers who will decide whether to make them law.

“I am sending the Congress a budget that rebuilds the military, eliminates the Defense [Department] sequester, and calls for one of the largest increases in national defense spending in American history,’ he said vaguely. “My budget will also increase funding for our veterans.”

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But that was it. And even the top line numbers his White House’s budget office sent to agencies were received with skepticism around Washington. For instance, McCain, chairman of the Senate Armed Services Committee, says he cannot support Trump’s plan because it calls for too little additional Pentagon funding.

And Mackenzie Eaglen, a former GOP Senate defense aide now with the conservative American Enterprise Institute, said its proposed increase would not be “enough to move the military needle even if Trump’s team rewrote the entire Obama budget for next year, which is highly unlikely given the condensed calendar.”

Another sign of trouble for Trump’s first spending blueprint: House Budget Chairwoman Diane Black said Tuesday the committee has begun work on the fiscal 2018 budget resolution, indicating it may have different spending levels than the White House’s proposal. “We are doing our own budget. The president does his own budget. We’ll see how they match at the end of the day.”

Senate Majority Leader Mitch McConnell said the Senate would “probably not” pass a budget that cuts State Department funding drastically. He is personally not in favor of cutting the department’s funding. He’s a former chairman of the Appropriations subcommittee that oversees State’s annual budget.

Ryan, about 11 hours before the president began speaking, downplayed notions that he and Trump have different plans to replace the 2010 health law.

“This is a plan that we are all working together — the House, Senate and the White House. So there aren’t rival plans here,” he told reporters. “I feel at the end of the day when we get everything done and right we’re going to be unified on this.”

Lindsey McPherson, Bridget Bowman, Rema Rahman, and Jennifer Shutt contributed to this report.