AMNA NAWAZ: The Supreme Court ruling against drawing congressional maps to protect Black or other minority voters has sparked a new wave in the ongoing redistricting war.

Our congressional correspondent Lisa Desjardins joins me now.

She's back at the super screen for a look at where things stand.

So, Lisa, walk us through it.

How has the map changed in the last month?

LISA DESJARDINS: I mean, this is a historic moment in terms of how we draw our political lines.

It could easily become a blur.

So let's start, first of all, with where this is happening.

Let's go back, oh, even a whole month ago.

This is what the map looked like.

You see these four states that were redrawing toward Republicans' favor, two that had maps that were moving toward Democrats' favor.

You can notice these were all over the country.

Then something happened two weeks ago.

We saw action in Virginia.

Voters there passed a Democratic-leaning map, and, in Florida, the governor and legislature moved to put in place Republican-leaning maps.

That was two weeks ago.

Then we had last week's Supreme Court decision.

Look at how this changes things.

Now we have four more states interested in remapping.

And look at that shape.

It used to be this debate was spread out all over the country, but now we see a real focus on one region of the country, the South.

That is the where.

Now let's talk about what this means.

All of this remapping is really about just changing the odds.

It's not a guarantee of picking up seats, but let's talk about how those odds could play out.

First of all, these are the states that have new maps in place right now.

This is the maximum amount of seats Republicans can gain, the maximum for Democrats.

Essentially, it's a wash, especially because many of these Republican seats are more risky.

They're going to be harder for Republicans to pick up.

Now, let's add in if those four states in the conversation because of the Supreme Court do redistrict.

What happens?

Look at this.

Republicans increase their odds significantly.

What it means is they have more of a chance of gaining on net, Amna, because of redistricting.

AMNA NAWAZ: They used the word if a lot.

LISA DESJARDINS: That's right.

AMNA NAWAZ: It seems there's a lot of uncertainty still ahead even with just months to go before those midterm elections.

So what happens next?

LISA DESJARDINS: I think I can clear this up.

Think of the states in play right now in two ways, first, the states that are having court battles.

I want to focus on three, the state of Virginia.

We're waiting on the state Supreme Court to rule on the map there.

Florida.

Florida has a law banning partisan gerrymandering.

So, no surprise, there are lawsuits there.

We will watch courts.

Now, Louisiana, how about this?

Early primary voting is under way.

The governor has moved to suspend it for House races.

But that's why we have lawsuits in place in Louisiana.

We could get information on any of these as soon as this week.

Now let's talk about places you should be watching the legislatures, first, Tennessee and Alabama, both of these states holding special sessions right now to talk about redistricting.

Alabama, notable that they also need help from the Supreme Court, needs to lift a previous injunction.

But they are acting as if they will get that action from the Supreme Court.

Finally, Mississippi, how about this?

Their primary was in March for those House races.

Those candidates are running their races for the fall.

But there is a special session there coming up in May.

AMNA NAWAZ: Lisa, what does ultimately all of this mean when it comes to minority representation, which the Voting Rights Act was meant to protect?

LISA DESJARDINS: That's right.

Now, this is a debate over -- of course.

But when you look at it in net, if all of this were to take place, it is highly likely that we'd see fewer Black and brown members of Congress next year.

One of those members of Congress whose district is likely targeted is in Alabama.

That's Terri Sewell.

REP.

TERRI SEWELL (D-AL): It will not only suppress minority votes in the halls of Congress, but it will erode minority representation in statehouses, city councils, and even school boards across this nation.

LISA DESJARDINS: Now, one way to look at this is about the current composition of these delegations.

Red - - these are the red Republican members of Congress from each state, blue, Democrats.

What does that matter?

Many of these blue districts are majority-minority districts drawn in part because of the Voting Rights Act.

Many of these are Black members of Congress.

Keep your eye on the center of this screen and you can see what happens if all of the redistricting that Republicans want goes into place.

Those blue districts disappear.

Now, Republicans say they think this is more fair.

They want to take race out of it, and they say they would like to recruit.

They're hopeful that perhaps they can get some Black and brown candidates.

But if they don't, those who support the Voting Rights Act say, this would be a historic shift.

We would see far fewer Black and brown members of Congress.

Perhaps the red and blue balance might not change, but the balance in terms of who is in Congress by race could.

AMNA NAWAZ: We know you will continue to follow this story in the weeks and months ahead.

Lisa Desjardins, thank you very much.

LISA DESJARDINS: You're welcome.