Republican presidential nominee Donald Trump arrives for his election night rally at the New York Hilton Midtown in Manhattan. (REUTERS/Andrew Kelly)

Donald Trump won the presidential race following a campaign where he promised to “drain the swamp” and break apart the so-called Washington establishment — but his election is likely to drive more business to the very Washington lobbyists he criticized.

In the short term, Trump’s stunning and unexpected victory is likely to be a boon to the lobbying business, despite his widespread unpopularity among Washington lobbyists of both political parties. That’s because political upheaval, uncertainty and a changeover of power in Washington heightens interest and concern from the business community over what agenda will be pursued by a new administration and Congress.

This is perhaps more true today than ever before because of Trump’s unpredictable and unorthodox policy stances.

This means lobbyists who were wary of Trump during the campaign will likely soon shelve those concerns and get down to business.

“You can sit on the sidelines and sulk and complain you don’t like him, or you can roll up your sleeves and realize he will be the president of the United States and he’s going to implement a pretty aggressive policy agenda,” said Marc Lampkin, a GOP lobbyist who chairs the lobbying practice at Brownstein Hyatt. “If you have client interests or broader policy interests, you’ve got to engage. You can’t be someone who’s going to exhibit a temper tantrum because you didn’t like the Trump that was portrayed in the media.”

Lampkin is among a small minority of K Street leaders who publicly backed Trump, hosting events to raise money for the campaign and huddling with Donald Trump Jr. in Washington recently to discuss strategy.

Once the dust settles, some industry sectors could greatly benefit from a Trump administration if he follows through with his stated intentions to roll back, for instance, environmental regulations initiated by President Obama.

In the long term, and in subtle ways, many lobbyists also see the Trump populist phenomenon reshaping their industry as well. Trump’s win is prompting many lobbyists to acknowledge that the long-held model of lobbying — sending well-connected hired guns to sell their clients’ message to powerful legislators or administration officials — is eroding, and must evolve to resonate with Americans outside the Beltway. The shift from traditional shoe-leather lobbying toward more social media, digital advocacy and public affairs has been underway for several years now, but Trump’s election is a clear signal this movement is far from over.

“The takeaway from this election is that there’s a disconnect between the Acela corridor and the rest of the country,” said Dave Tamasi, a GOP lobbyist who served as finance chair for Trump Victory fund. “The real thing here for an advocate worth his or her salt is to be able to articulate how the policies they’re advocating for are going to have an impact on the rest of the country and not just a select few.”

Trump’s election now raises the question of whether he will welcome lobbyists into his administration, or stay true to his anti-Washington campaign rhetoric.

Also hanging over the lobbying world is to what degree Congress will embrace his call during the campaign for a crackdown on the influence industry.

Last month, Trump announced proposals aimed at closing the revolving door between government and the lobbying industry that go well beyond current ethics rules. He called for a five-year ban on members of Congress and executive branch officials who want to become lobbyists after leaving government, and a lifetime ban on senior executive branch officials from lobbying for foreign governments. He also sought to close a loophole in federal lobbying law that allows people who spend less than 20 percent of their time lobbying to call themselves something other than a lobbyist, such as a consultant or adviser.

When the proposals were announced they were considered highly unlikely to be put in place because any changes to federal lobbying laws would have to be passed by Congress. They also only focus on government officials and lawmakers joining the lobbying industry, but do not address rules about lobbyists joining the administration.

But if Trump presses for lawmakers to implement his proposals, Congress may find it difficult to do nothing, given his victory was in part due to voters’ support for his promise to shake-up the status quo in Washington.