The Note: Trump's talk brings impeachment back into play The candidate who may crave impeachment the most is Trump.

The TAKE with Rick Klein

Impeachment for congressional Democrats is a story of the "Peanuts'" Lucy and the football, only in reverse. They keep trying to clear the field for their 2020 contenders, only to have President Donald Trump tee them up all over again.

This time, with overt actions that appear to call on a foreign government to investigate a political opponent, Trump has made the stakes more urgent and the politics less clear.

This is not a standoff about obscure constitutional prerogatives or petty score-settling. Trump's behavior in this episode has immediate implications on foreign policy -- with the president at the United Nations General Assembly this week -- and raises questions about what else he might do over the 13-plus months before next November's election.

Congressional Democrats this week are preparing for their oversight efforts to be thwarted in novel and potentially troublesome ways. House Speaker Nancy Pelosi is recognizing that dynamic, with a letter to colleagues warning that blocking a whistleblower's complaint from Congress would bring "a whole new stage of investigation."

The Democrats running for president are leading the calls for impeachment. Again, though, the candidate who may crave impeachment the most is Trump.

Absent massive Republican defections, the president knows how the game ends, even as Democrats struggle with whether the plays are worth pursuing.

The RUNDOWN with Alisa Wiersema

Steaks weren't the only things being grilled at this weekend's Steak Fry in Iowa -- so was current Democratic front-runner Joe Biden.

The former vice president kicked off one of the first, major political events of the campaign cycle by going on offense over the fallout of a whistleblower scandal involving President Donald Trump, Biden's son, Hunter, and Ukraine. In a crowded gaggle on Saturday, Biden snapped at reporters when asked about allegations that the president pressured Ukraine to investigate his son as part of an effort to seek information that could be damaging to Biden.

"You should be asking him the question: Why is he on the phone with a foreign leader, trying to intimidate a foreign leader?" Biden said. "This appears to be an overwhelming abuse of power."

Biden's campaign has always touted him as being the toughest challenger to Trump, but that brand may present new hurdles as Biden (along with his family) faces more scrutiny despite having been in the public eye for decades.

For now, Biden is still going above the primary fray, and focusing on Trump rather than his Democratic challengers. At his last campaign event of the weekend, he deflected on a question about his son and Ukraine.

"Focus on the violation of the Constitution this president is engaged in," Biden said.

The TIP with Beatrice Peterson

Sen. Cory Booker's campaign manager announced Sunday night on Periscope that the candidate had raised $425,000 over the weekend, almost 25% of the $1.7 million they said they needed by Sept. 30 to stay in the race. This announcement came one day after the campaign sent out dire warnings via a Medium post about the campaign's fate if it didn't raise $1.7 million.

To put that haul into perspective, some top campaigns have said that they raise six figures just from sending an email. Booker has just seven days to reach his goal.

Addisu Demissie, Booker's campaign manager, in an email on Sunday said that Saturday was "the best single online fundraising day of our campaign, bigger than even the launch of this campaign on February 1." He acknowledged that there's "still a long way to go," but they can tackle tough challenges.

Only time will tell if Booker will make his goal, but he has the support of one former 2020 candidate Sen. Kirstin Gillibrand, who urged people to donate.

THE PLAYLIST

ABC News' "Start Here" podcast. Monday morning's episode features ABC News Senior Editorial Producer John Santucci and ABC News Political Director Rick Klein on the fallout from a whistleblower complaint against President Donald Trump and the growing calls for his impeachment. Then, ABC News' Rachel Scott checks in from Iowa to talk about Sen. Elizabeth Warren building momentum in the Democratic primary. http://apple.co/2HPocUL

WHAT YOU NEED TO KNOW TODAY

President Donald Trump is in New York City for the U.N. General Assembly. He'll lead the event on religious freedom at the United Nations Headquarters at 11:30 a.m. Then he'll participate in several meetings at the InterContinental New York Barclay Hotel with various world leaders including President Arif Alvi of Pakistan, President Andrzej Duda of Poland, Prime Minister Jacinda Ardern of New Zealand, President Halimah Yacob of Singapore, President Abdel Fattah el-Sisi of Egypt and President Moon Jae-in of South Korea.

First lady Melania Trump rings the opening bell at the New York Stock Exchange at 9:30 a.m.

Sen. Bernie Sanders, I-Vt., starts his "Bernie Beats Trump" tour in Iowa. First he holds an assembly at Northwood-Kensett Jr.-Sr. High School in Northwood, Iowa, at 10:30 a.m. (CST). He has a town hall at Luther College in Decorah at 1 p.m. and then an ice cream social at Town Clock Plaza in Dubuque at 4:30 p.m. Later, he has a rally at the Clinton Masonic Center in Clinton at 7:15 p.m.

Former Rep. Beto O'Rourke, D-Texas, has a roundtable with parent advocates from "Purpose Over Pain" in Chicago. He also has a town hall in Gary, Indiana, at J's Breakfast Club at noon. (CST).

South Bend, Indiana, Mayor Pete Buttigieg is in Iowa and hosts a "Meet Pete" event at the Elkader Opera House at 1:30 p.m. (CST). He then has a town hall at the Alliant Energy Amphitheater in Dubuque at 6 p.m.

Republican presidential candidate and former South Carolina Gov. Mark Sanford visits the Coralville Farmers' Market in Coralville, Iowa, at 5 p.m. (CST).

Former Vice President Joe Biden attends a funeral service for Dr. Emily Clyburn, civil rights activist and wife to Rep. Jim Clyburn, in Charleston, South Carolina. Later he has a fundraising event in Philadelphia.

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The Note is a daily ABC News feature that highlights the day's top stories in politics. Please check back tomorrow for the latest.