GEOFF BENNETT: Congress is facing a long holiday to-do list, from budgets and health care to foreign affairs, all while Republican leaders contend with growing frustration and even open rebellion within their ranks.

Lisa Desjardins has more.

GROUP: Five, four, three, two, one.

REP.

MIKE JOHNSON (R-LA): There you go.

(CHEERING) LISA DESJARDINS: The season of light is under way outside the Capitol, but there are shadows and restlessness inside, especially for House Republicans and their speaker, Mike Johnson.

He has key defenders.

REP.

RALPH NORMAN (R-SC): Look, Mike's job is like nailing Jell-O to a wall.

He's done a good job.

REP.

MIKE FLOOD (R-NE): If you look at what our goals were when this Congress started, we have achieved almost all of the ones that were initially set out.

LISA DESJARDINS: But on social media, anger and worse, like from New York Republican Elise Stefanik, who this week called Johnson a liar.

Another congresswoman, Marjorie Taylor Greene, backed her up, writing that: "The speaker breaks his promises."

Greene recently announced her resignation, among her concerns, that, during the government shutdown, as Johnson held daily news conferences, he kept the full House out of session for nearly two months, and he blocked popular bills, like the one releasing the Epstein files.

Republican Thomas Massie of Kentucky co-sponsored that.

REP.

THOMAS MASSIE (R-KY): He's been basically just doing whatever President Trump wants to do.

So I would say President Trump's been in control of the House.

LISA DESJARDINS: Johnson points to the numbers.

REP.

MIKE JOHNSON: When you have a razor-thin majority, which we have, this is not like the old days.

In the old days, they had 30-, 40-seat majorities, and so four leaders could go in a back room, create the agenda, and foist it upon everybody and say, this is what you're doing.

LISA DESJARDINS: But other Republicans say that is exactly what's happened.

They are increasingly going around Johnson.

REP.

THOMAS MASSIE: Well, I have been here 13 years, and I have never tried to use a discharge petition, but it became apparent to me that that was a legitimate tool and that it could succeed.

LISA DESJARDINS: Buried in the House rules, discharge motions allow a majority of House members to sign a petition and force a House floor vote on a bill.

Just a handful have ever succeeded.

But in just the last two years, five discharge petitions have made the 218-signature threshold.

This week, Representative Anna Paulina Luna announced she will attempt a discharge petition on another popular and blocked bill, one to ban stock trading by members of Congress.

Not everyone is comfortable with this.

REP.

MIKE FLOOD: I'm a former speaker of the Nebraska legislature.

I know what it's like to run a legislative body.

And that's not how it should work.

LISA DESJARDINS: But, increasingly, more Republicans say this is the way to get Johnson and Trump's attention.

REP.

DON BACON (R-NE): If the White House took our input, I think they have been in a strong position.

This is a way for us to put in our input.

LISA DESJARDINS: Now, the dynamics for House Republicans aren't just palace intrigue.

They will determine if and how the House addresses those Affordable Care Act subsidies, due to expire for millions at the end of this month.

GEOFF BENNETT: And, Lisa, you have been talking with House Republicans this past week about Speaker Johnson.

How serious are their concerns?

LISA DESJARDINS: This is a real test.

We have seen Speaker Johnson navigate, seemingly even against the odds, some of the policy concerns, get through very large bills this year, but this is his biggest political test.

I was amazed in the past week, over the holiday week, how many of my Republican sources, rank and file, and senior Republicans were texting me about their discontent, even raising possible ouster -- no one's really going that far, but it's in the air right now -- of Speaker Johnson.

So this is a real test.

Today, I caught up with him, and he told me exclusively sort of how he's reacting to these public and private calls from discontent.

REP.

MIKE JOHNSON: A lot of people disagree with us staying home during the shutdown.

But we won the shutdown because of that.

And in a midterm cycle, you have very small margins, and people have their emotions and all that.

But you can always find a few people who are disgruntled about things.

LISA DESJARDINS: And that's true, but the key for Republicans especially, if you're Republican speaker in this century, you got to make sure that doesn't grow.

Now, what does this matter?

It doesn't just affect him and his leadership, but it also affects big issues.

I mentioned health care, also Ukraine, Russia and, of course, what Republicans present going into a critical election year next year.

GEOFF BENNETT: And we heard the speaker mention the slim GOP margins.

Republicans picked up a win last night in that closely watched special election in Tennessee.

Tell us about it.

LISA DESJARDINS: What an interesting race.

There's something for each party in this race, but in the end the winner of this race, Matt Van Epps, who is a veteran, former Army helicopter pilot, was able to win by nine points.

That sure sounds like a lot doesn't it?

No, this is a deep red district where the former congressman, a Republican, won by 22 points.

It's pretty easy math.

That's a 13-point slide for Republicans in red Trump territory.

Trump in fact himself came in and tried to help with this race.

So did Speaker Johnson.

They were able to win it.

But this is something that, when I talked to my Democratic sources last night, they said they were ecstatic about being within nine points.

And it really expands the group of potentially vulnerable Republicans.

There are more than 30 who in the last midterm election lost their race by 13 points or fewer.

So we will see what it means.

It's a special election.

It's not the same as a midterm, but Democrats like the enthusiasm they saw from their voters last night.

GEOFF BENNETT: Lisa Desjardins, our thanks to you, as always.

LISA DESJARDINS: You're welcome.