The Note: The country waits for Biden and Mueller while Democrats forge ahead

The TAKE with MaryAlice Parks

On Capitol Hill or the campaign trail, politicians and lawmakers this week forged ahead as big unknowns loomed.

The Democrats already running for president expanded the map -- with early visits to Texas, California and the Deep South in the works -- and expanded the universe of discussion topics too.

Abolishing the Electoral College? Growing the Supreme Court? Yes, Democrats will go there it seems.

But as much as these candidates settled into new staffs and pitched new ideas, the question about whether the familiar, former vice president would jump in lingered.

Meanwhile, congressional investigators kept up the pressure on the White House. Democratic Chairman Elijah Cummings demanded more information about Jared Kushner’s alleged use of personal email and encrypted messaging services while working in his official White House role.

After all, Democrats in key committees have promised to conduct their own oversight of this administration, amid the ongoing anticipation of a final report from special counsel Robert Mueller that's hanging over the nation’s capital.

The RUNDOWN with John Verhovek

This week President Donald Trump ignored concerted push back from his own party, continuing to criticize the late Sen. John McCain months after the revered statesmen's passing.

"It's deplorable what he said," the normally reserved Georgia Sen. Johnny Isakson said Wednesday.

"Mr. President, seriously, stop talking about Senator McCain," freshman Texas Congressman Dan Crenshaw pleaded.

But despite the round of hand wringing from the GOP, the appetite for a primary challenge to Trump remains unclear and without a clear successor waiting in the wings.

Maryland Gov. Larry Hogan, who told ABC News earlier this month that he isn't currently pursuing a presidential bid but hasn't ruled it out, as former Massachusetts Gov. Bill Weld and former Ohio Gov. John Kasich remain the most-discussed potential challengers.

Hogan and Kasich got a push toward a presidential bid from an unlikely source this week, when Democratic presidential candidate and former Maryland Congressman John Delaney released a statement urging him to primary Trump, writing: "Voices like John Kasich and Governor Hogan, from my state, would do an enormous service to not just their party but to their fellow Americans to stand up and challenge this president."

The TIP with Kendall Karson

Democratic hopeful Elizabeth Warren, distinguished for her pace-setting policy proposals, returns to New Hampshire this weekend to bring another issue into the foreground: the opioid crisis.

Warren is set to hold a discussion Saturday in Littleton, a town of nearly 6,000 people, in a state that is home to the second-highest rate of opioid-related overdose deaths in the country, according to the National Institute on Drug Abuse.

The Massachusetts senator's visit comes on the heels of another 2020 contender's commitment to holding drug manufacturers responsible for their role in the crisis.

"What we have to do is take on the drug manufacturers, who purposefully made these drugs stronger and more addictive," Gillibrand said at an MSNBC town hall.

THE PLAYLIST

ABC News' "Start Here" Podcast. Friday morning’s episode features ABC News Chief White House Correspondent Jonathan Karl, who tells us how a letter from Rod Rosenstein could provide a road map to the Mueller report. Then, ABC News Chief National correspondent Matt Gutman and ABC News' Jordana Miller in Jerusalem explain Trump's decision to recognize Israel’s sovereignty over the Golan Heights. ABC News' "Start Here" Podcast. http://apple.co/2HPocUL

WHAT YOU NEED TO KNOW TODAY

2020 hopefuls on the campaign trail this weekend:

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