Meeting in the Oval Office on Wednesday are, clockwise from...

Meeting in the Oval Office on Wednesday are, clockwise from left, House Majority Leader Kevin McCarthy, R-Calif., Vice President Mike Pence, President Donald Trump, Senate Majority Leader Mitch McConnell, R-Ky., Senate Minority Leader Charles Schumer, D-N.Y., and House Minority Leader Nancy Pelosi, D-Calif. Credit: Washington Post/Bill O’Leary

Shortly before Hurricane Irma hit the U.S. mainland, the latest waves of Hurricane Trump hit Washington, reshaping political battle lines in a totally unexpected but potentially productive way.

Many analysts wonder if Trump’s new alliance with Democratic congressional leaders can persist past last week’s success in raising the debt ceiling, funding the government and making a down payment on Hurricane Harvey reconstruction. After all, these measures HAD to be passed, as opposed to those the president would LIKE to pass.

But it may recur because it reflects two institutional realities that almost certainly will ultimately force the president to seek Democratic votes.

- Senate rules requiring 60 votes for most legislation mean that GOP leaders will generally need more than the 52 Republicans. They weren’t enough for the special procedure Majority Leader Mitch McConnell used in the effort to repeal-and-replace Obamacare. Except for a few months in 2009, neither party has had 60 votes in nearly 40 years.

- The House GOP’s adherence to the so-called Hastert Rule. That is, the refusal to consider measures without support from a majority of Republicans, has weakened the chamber’s clout in recent years by preventing consideration of measures with broader support.

Throughout the Obama years, House Republicans repeatedly passed legislation reflecting the views of a majority of their members, who hail primarily from heavily Republican districts. Multiple appropriations bills cutting social programs and other conservative measures died in the Senate because they failed to attract enough bipartisan support to get the 60 votes needed to surmount the Senate’s rule allowing unlimited debate.

On health care, Republican leaders sought to act with only GOP votes, using the rule that allows a reconciliation bill implementing the annual budget resolution to pass each house with a simple majority, meaning 51 in the Senate.

But increased GOP congressional numbers have broadened the party’s ideological coalition, requiring the conservative majority to make compromises with more moderate members. That’s how House Republican leaders succeeded in passing Obamacare repeal on their second try, but the legislation cut too many benefits from too many people for some Senate Republicans.

The failure angered Trump, who is far more interested in results than ideological purity. If he had been better prepared for his presidency and been able to set his own congressional priorities, he might have put tax reform or infrastructure reconstruction before Obamacare.

White House legislative director Marc Short conceded Tuesday at a breakfast session with reporters sponsored by The Christian Science Monitor that the Obamacare experience showed the difficulty of trying to pass major legislation with only GOP votes, something likely to become increasingly evident in the months to come. Though Trump’s initial infrastructure plan relies more on private and state funds than federal money, it’s still too costly for many House Republicans. But Democrats won’t support repairing the nation’s roads and bridges without a significant influx of additional federal money.

Short said Republicans are still planning to pass tax reform via reconciliation, which would only require GOP votes, but added that the White House plans to reach out for bipartisan backing and is not assuming it can be done “strictly on a partisan basis.” On Tuesday night, Trump hosted three moderate Democratic senators from red states he carried last year.

Meanwhile, the need for additional billions for hurricane relief may complicate prospects for any Republican tax bill that cuts rates so much it costs the government far more in revenue than it recovers from closing loopholes.

Trump will also need bipartisan support for his announced intention of protecting the Dreamers - from his own administration’s decision ending their protection from deportation. Indeed, many Republicans won’t support it unless it is part of a broader immigration bill.

That’s probably why Short indicated that Trump wants to include enhanced border security - though not necessarily his controversial plan for a wall - in any legislation protecting the Dreamers brought to the United States illegally as children. In 2013, a bipartisan Senate-passed immigration bill might have passed the House, but GOP leaders killed it by invoking the Hastert rule and refusing to bring it to the floor.

Forming additional bipartisan majorities like Trump and the Democrats created last week won’t be easy. It will require cooperation from GOP leaders, who control the calendar in both houses. It will be necessary for the only measure Congress MUST pass in December, a bill funding the government for the rest of the fiscal year.

That’s why, for Trump, reality requires that he continue to look beyond his Republican majorities if he wants to get things done.

Carl P. Leubsdorf is the former Washington bureau chief of the Dallas Morning News.