(CNN) 5. Abortion emerging as an issue: With Alabama passing legislation last week that effectively banned abortion (with the lone exception of when the life of the mother is in danger), the issue roared back into the conversation on the campaign trail.

The two questions now: How long will it last and will one Democratic candidate emerge as the voice of the opposition in the abortion fight.

On the first one, it seems likely that abortion will remain front and center -- due in large part to a series of laws passed by Republican-controlled state governments in Ohio, Georgia and Missouri, among others.

On the second, it's tougher to predict -- although New York Sen. Kirsten Gillibrand is clearly hoping to use the issue as a momentum springboard. She traveled to Georgia last week to protest that state's passage of a fetal heartbeat bill, condemning the "nationwide assault on women's constitutional rights by ideological extremists."

You might have missed Steve Bullock's entry into the 2020 race last week. Which is understandable because the Montana governor is not seen as a top- (or even second-) tier candidate.

With SO many Democrats running, my guess is there will be more lower-tier candidates like Bullock who try to camp out in either Iowa or New Hampshire -- the first two states to vote -- in hopes that lavishing a single state with all their time and money will lead to a surprisingly strong finish.

3. Trump goes to Pennsylvania: As he ramps up his 2020 campaign -- in truth he never really ramped it down -- the president will hold a rally in Montoursville, Pennsylvania Monday night.

That rally follows one earlier this month in Panama City Beach, Florida . And one late last month in Green Bay, Wisconsin. A month before that -- late March -- Trump held a rally in Grand Rapids, Michigan.

Remember that a president's time is the most valuable resource in any reelection campaign. So if you need to know where the Trump team thinks the election is going to be won and lost, just look at where the President has spent his time at rallies so far this year.

Trump won all four states -- Pennsylvania, Wisconsin, Michigan and Florida -- in 2016. He probably needs at least two of those four -- and maybe three -- to win a second term. And his campaign team knows it.

2. You get a town hall! And you get a town hall!: Starting Sunday night, there will be three town halls this week featuring three different 2020 Democrats on three different networks.

South Bend Mayor Pete Buttigieg kicks things off tonight with a Fox News town hall in New Hampshire. (Buttigieg is the third Democrat to participate in a Fox town hall -- following Sens. Bernie Sanders of Vermont and Amy Klobuchar of Minnesota.) Sen. Elizabeth Warren of Massachusetts very publicly said last week she would not participate in a Fox News-sponsored town hall.

On Tuesday, it's former Texas Rep. Beto O'Rourke's turn, as he is featured in a CNN town hall in Iowa. Two days later, New Jersey Sen. Cory Booker is in Iowa for an MSNBC town hall.

Why so many town halls? Networks love them because they do well in ratings. Candidates love them because it's an hour, uninterrupted, on national TV -- a chance to build momentum (in the case of Booker and O'Rourke) or keep it up (Buttigieg).

1. Biden (and the rest): The former vice president officially entered the presidential race (although he was already in!) over the weekend, with a kickoff speech in Philadelphia.

Here's the key bit:

"Some say Democrats don't want to hear about unity. That they are angry -- and the angrier you are -- the better. That's what they are saying to have to do to win the Democratic nomination. Well, I don't believe it. I believe Democrats want to unify this nation."

That message is aimed squarely at the party's most liberal voters -- and 2020 candidates -- who see Biden's appeal to electability as a red herring. But Biden is clearly framing the race on these terms -- I am the one who can beat Trump -- and forcing the other candidates to prove him wrong.