This week, with senators returning to Washington to try to pass a fourth coronavirus relief package, Jim Newell, who covers Congress for Slate, he says it's worth keeping in mind that a third of these senators, they're up for re-election.

Jim, if I'd talk to you about what the 2020 Senate prospects looked like a month ago, what would you have said?

I would have said kind of close to a coin flip.

Senate Majority Leader Mitch McConnell, he's on the ballot this fall.

Same with Republicans from Maine, Colorado, Arizona.

I would have called it a target-rich environment, but... What do you mean by that?

Well, the Republicans have more seats up this time, but it's hard to find sort of the tipping

point race that could give Democrats control of the Senate.

So for Democrats, at the Senate. So for Democrats, at the same time, they are figuring out the math of how to get enough

relief to small businesses, how to keep unemployment checks flowing.

In the back of their minds, they're also doing this other math, how to gain control in Washington.

If they can hold onto the seats they've got, they need to gain three more to even up the ranks.

But as this new coronavirus spread around the country, and as Joe Biden took control of the top of the 2020 ticket, something funny started happening for Dems. Their math started to change. The whole reason we are talking about Democrats potentially having a shot at flipping the Senate, which seemed not so long ago like a distant, almost fantastical dream.

It all comes down to money, right?

Yes.

What kind of money are we talking about?

One example is Mark Kelly, who is the astronaut husband of Gabby Giffords,

the former Congresswoman.

He's running against Martha McSally in Arizona, and he raised $11 million in the first quarter and has $20 million on hand.

Now, that's a lot of money.

And you're seeing a lot of candidates, too.

I mean, you see Sarah Gideon

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