By Jeff Mason

NEW YORK, Sept 24 (Reuters) - President Donald Trump and his people were ready for the day Democrats decided to launch an impeachment inquiry against him.

Trump's re-election campaign raised a quarter of a million dollars in just 15 minutes on Tuesday in the immediate aftermath of House of Representatives Speaker Nancy Pelosi's announcement about the probe.

The president, tweeting from Trump Tower in New York where he launched his 2016 campaign for the White House, blasted out a video shortly after she finished that highlighted how Democrats had talked about pushing him out for 2-1/2 years.

Far from exuding an aura of concern that might accompany the disclosure that a president faced formal efforts to remove him from power, Trump's advisers appeared full of bravado and almost pleased by the news.

“We had a lot of things prepared just in case the Democrats were, in fact, that stupid. And in fact, they were,” said Tim Murtaugh, the Trump campaign's communications director, reacting to the impeachment process and disclosing the campaign's early cash haul.

"So we’re probably going to have a tremendous fundraising surge. We think that this gets the president just that much closer to a landslide victory.”

The campaign prepared the video Trump tweeted some six weeks ago, he said, long before the latest controversy over his call with Ukraine President Volodymyr Zelenskiy in July.

With the impeachment inquiry, Democrats are leveling serious charges against Trump, accusing him of seeking Ukraine's help to investigate Democratic presidential front-runner Joe Biden and his son Hunter, who had business in the country, in hopes of damaging Biden's candidacy ahead of next year's election.

"The president must be held accountable. No one is above the law," said Pelosi, who for months had been reluctant to embrace an impeachment effort.

Trump, who in a tweet after Pelosi's announcement, labeled the probe "Witch Hunt garbage," also appeared to embrace the argument that the impeachment effort could help his 2020 prospects.

"They all say that’s a positive for me, for the election," Trump told reporters in New York. "But the good news is, the voters get it. This is why they say it's good for the election. But you know what? It's bad for the country."

'DEVIL IN THE DETAILS'

The Republican National Committee pointed to polling from Monmouth University in late August that showed low support for impeachment among the public.

That sentiment, along with the fact that the Republican-controlled Senate almost certainly would not convict Trump if the Democratic-led House went so far as to impeach him, had previously weighed on Pelosi, who long resisted calls from left-leaning colleagues to make a move.