The Note: Everything is riding on tax reform for Republicans

— -- THE TAKE with ABC News' Rick Klein

The push for tax reform is intensifying on Capitol Hill, with White House economic adviser Gary Cohn and Treasury Secretary Steven Mnuchin making a fresh effort today to clear the way for a bill sooner rather than later. As they arrive, the stakes have expanded accordingly, if not exponentially. President Trump over the weekend cited the storms as another reason for a "speedup," as part of his push to see progress on a bill by the end of the month. He didn't need any hurricanes to find urgency, though. Tax reform – or, at the very least, a major tax cut – has become just about everything for the Republican Party. It's being asked to juice the economy; settle nerves on Wall Street; unite the GOP's warring factions (Trump, Cohn, Paul Ryan, and Mitch McConnell can all be friends again); and demonstrate that Republicans are capable of passing something – anything at all – in the Trump era. Think through what happens if a bill falls short and you realize quickly what must-pass feels like for Republicans. Mnuchin rubbed GOP lawmakers the wrong way last week when he asked them to vote for the debt ceiling/Harvey aid compromise "for me." On taxes, the votes will be for all of them.

SINGLE PAYER GETS SOME HEAVY HITTERS

Oh, how the tables have turned – to the left. Last go-around, before anyone felt "the Bern" and marched to "resist" the man in the White House, independent Vermont Sen. Bernie Sanders could not get a single additional co-sponsor on his bill for a universal, single-payer, Medicare-for-all-style health care system. During the presidential primary, he was repeatedly attacked by Democrats for his proposal. They argued his plan would be too disruptive, too astronomically expensive. It was cast as disloyalty toward President Obama's Affordable Care Act, which was under sufficient attack by Republicans. But now, a glance at the names of those joining Sanders makes clear how much the power and momentum in the Democratic Party is shifting to the left. Sanders will introduce his latest single-payer bill Wednesday, with enough co-sponsors to fill a presidential debate stage. "Who do we have now? [Kirsten] Gillibrand, [Cory]Booker, [Elizabeth] Warren, Kamala Harris, Bernie Sanders. Is there anyone else who is possibly running for president in 2020?" Sanders' Capitol Hill spokesman told ABC News Monday, ABC News' MaryAlice Parks reports. "That now will mean that the conversation about single payer, Medicare-for-all is at the heart of the Democratic Party."

MAKING OF A WAVE?

The year 2018 may be a long way off but recent retirements by a succession of moderate GOP members in the House may be just the start of a broader wave taking shape. In the last week, Reps. Dave Reichert of Washington, Charlie Dent of Pennsylvania and Dave Trott of Michigan, all Republicans, have announced they are not seeking re-election in 2018. Retirements are a fact of political life; 22 house members on average have retired each cycle since 1976, according to Inside Elections. So what makes these retirements different? Geography. Hillary Clinton won Reichert's district in 2016, and came within striking distance in Dent and Trott's districts. Clinton also won Florida's 27th congressional district, represented by longtime moderate Republican Ileana Ros-Lehtinen, who announced her retirement earlier this year, by nearly 20 points. So while retirements are expected, the National Republican Congressional Committee can't be thrilled with who has chosen not to seek re-election this year. But it remains to be seen whether national Democrats can capitalize on a map slowly but surely shifting in their favor, ABC News' John Verhovek notes.

WHAT YOU NEED TO KNOW TODAY

QUOTE OF THE DAY

"We've been clear on what our position is and certainly, that has been shown in the days that followed that the president was right in firing Director Comey." -- Press secretary Sarah Sanders on Steve Bannon's suggestion that firing Comey was the biggest mistake in "modern political history"

NEED TO READ with ABC News' Paola Chavez

Trump Organization "still assessing" whether properties were damaged by Hurricane Irma. The Trump Organization is "still assessing" whether any of its properties incurred serious damage as Hurricane Irma tore through South Florida over the weekend. President Donald Trump owns four properties in Florida that made preparations prior to Irma's landfall. Separately, the president owns a vacation home on the island of St. Martin, which faced a devastating direct hit from Irma late last week. "Our teams in both Florida and St. Martin were very well prepared and we are proud of their efforts on the ground," a Trump Organization spokesman told ABC News Monday. "We are currently still assessing the situation at the properties that were in the storm's path and at this time we continue to send our thoughts and prayers to all of the victims." http://abcn.ws/2wWhmWm

White House declines to say whether climate change may have been a factor in recent hurricanes. After two back-to-back major hurricanes battered the coasts of Texas, Louisiana and Florida within the space of two weeks, the White House decline to answer questions Monday about whether climate change may have been a factor in the ferocious storms. When at the White House press briefing Monday a reporter asked whether the two destructive hurricanes have changed the administration's position regarding climate change, Homeland Security Adviser Tom Bossert said that the issue is taken "seriously" but declined to spell out the administration's position. http://abcn.ws/2xWfScj

Trump presides over his 1st 9/11 ceremony as president. President Donald Trump and first lady Melania Trump attended a commemoration ceremony Monday morning at the National 9/11 Pentagon Memorial, marking the 16th anniversary of the Sept. 11 terrorist attacks. http://abcn.ws/2wT90i4

Some Trump lawyers wanted Kushner out. Wall Street Journal

Exclusive: Hillary Clinton says Trump associates helped Russia meddle in the 2016 election. USA Today

McConnell says Democrats' glee on debt limit deal was premature. The New York Times

Stan Smith, De Niro help Lutnick through a tough week. Bloomberg

The Note is a daily ABC News feature that highlights the key political moments of the day ahead. Please check back tomorrow for the latest.