What polls show about the undecided voters who could swing the Senate

After months of campaigning and billions in TV advertising, it might be hard to believe that there are still voters up for grabs in the midterms.

But undecided voters are out there — and they're poised to be decisive in the fight to control the Senate next year, in addition to swinging key House and governor's races.

In the latest POLITICO/Morning Consult poll, 11 percent of voters nationwide said they were undecided about which party's candidate to support for Congress. So who are they, and is there any sign about which way they could tilt in the final week of the campaign?

The news isn't good for Democrats, according to the poll, which was conducted Oct. 21-23. Undecided voters overwhelmingly believe the country is off on the wrong track: 83 percent of those undecided on the generic ballot say so. Sixty-two percent of generic-ballot undecideds disapprove of the job Joe Biden is doing as president, and 60 percent have an unfavorable opinion of House Speaker Nancy Pelosi. (The poll was conducted prior to the attack on Pelosi's husband in their San Francisco home on Friday.)

That doesn't mean all the undecideds are going to vote for Republican candidates. In fact, many of them probably won't vote at all: A full quarter of undecideds, 25 percent, say they're "not at all enthusiastic" about voting in the midterms, compared to just 6 percent of all registered voters in the POLITICO/Morning Consult survey. Only 8 percent say they're "extremely enthusiastic" about their midterm ballot, compared to 38 percent of voters supporting the Democratic candidate and 40 percent backing the Republican.

But that, in and of itself, might be a problem for Democrats, since some of the key demographic groups they need to win are more likely to be undecided. Nearly a quarter of "Generation Z" voters — those born in 1997 or later — are undecided. Hispanic (22 percent) and Black (15 percent) voters are more likely to be undecided on the generic ballot than white voters (10 percent).

And now, our weekly update of the polling in the states that will decide the Senate majority:

1.

Arizona

MARK KELLY (D) vs. Blake Masters (R)POLITICO Election Forecast rating: Toss Up (Last week: Lean Democratic)RCP polling average: Kelly +1.5 (Last week: Kelly +2.5)2020 RCP polling average 10 days before the election: Biden +2.4Eventual margin: Biden +0.3

Although Democratic Sen. Mark Kelly led by larger, more consistent margins a month or two ago, Republican Blake Masters has closed much of the gap.

Dating back to the August primary, Masters has never led in any publicly disclosed poll. But a survey from the Democratic firm Data for Progress this week showed the two men knotted up at 47 percent apiece.

In that survey, 4 percent of voters were undecided, and 3 percent supported the Libertarian candidate, Marc Victor.

POLITICO's Election Forecast reclassified the race this week, changing its rating from "Lean Democratic" to "Toss Up."

2.

Colorado

MICHAEL BENNET (D) vs. Joe O'Dea (R)POLITICO Election Forecast rating: Lean DemocraticRCP polling average: Bennet +7.5 (Last week: Bennet +7.7)2020 RCP polling average 10 days before the election: No averageEventual margin: Biden +13.5

There were no new polls this week in Colorado, where older survey data suggested Democratic Sen. Michael Bennet had a lead over Republican Joe O'Dea.

3.

Florida

MARCO RUBIO (R) vs. Val Demings (D)POLITICO Election Forecast rating: Lean RepublicanRCP polling average: Rubio +7.4 (Last week: Rubio +5.7)2020 RCP polling average 10 days before the election: Biden +1.5Eventual margin: Trump +3.3

Two polls this week staked GOP Sen. Marco Rubio to leads over Democratic Rep. Val Demings: Rubio led Demings by 7 points in a Data for Progress poll, and by 11 points in a University of North Florida survey.

Only 3 percent of voters were undecided the University of North Florida poll, but that notably includes 18 percent of all voters under 25 years old, and 8 percent of Black voters.

4.

Georgia

RAPHAEL WARNOCK (D) vs. Herschel Walker (R)POLITICO Election Forecast rating: Toss UpRCP polling average: Walker +1.6 (Last week: Warnock +2.4)2020 RCP polling average 10 days before the election: Biden +0.8Eventual margin: Biden +0.3

Republican Herschel Walker has seized the lead in the RealClearPolitics average over Democratic Sen. Raphael Warnock, though the three most-recent polls in the average are from Republican or conservative-leaning firms (and that doesn't include an internal survey released by the National Republican Senatorial Committee).

Still, Senate Majority Leader Chuck Schumer acknowledged that the party is "going downhill" in Georgia, in a hot-mic moment with President Joe Biden on an airport tarmac in Syracuse, N.Y.

Regardless of which candidate has the lead, the number to watch is 50 percent: The leader needs to capture of a majority of all votes cast to win — otherwise, Walker and Warnock will meet again in a December runoff.

5.

Nevada

CATHERINE CORTEZ MASTO (D) vs. Adam Laxalt (R)POLITICO Election Forecast rating: Toss UpRCP polling average: Laxalt +1.2 (Last week: Laxalt +1.2)2020 RCP polling average 10 days before the election: Biden +5.2Eventual margin: Biden +2.7

The average in Nevada was unchanged this week, though a poll from the Republican-favoring Trafalgar Group gave Republican Adam Laxalt a 4-point lead, tying the biggest advantage Laxalt has posted in any public survey. (The other poll in which Laxalt led Democratic Sen. Catherine Cortez Masto by that large a margin was an older Trafalgar poll.)

6.

New Hampshire

MAGGIE HASSAN (D) vs. Don Bolduc (R)POLITICO Election Forecast rating: Lean DemocraticRCP polling average: Hassan +3.4 (Last week: Hassan +5.4)2020 RCP polling average 10 days before the election: No averageEventual margin: Biden +7

We've seen some tightening in New Hampshire, where Democratic Sen. Maggie Hassan's average lead over Republican Don Bolduc shrank 2 percentage points over the past week.

And that average doesn't include a survey from the Republican-leaning firm co/efficient for an in-state conservative media outlet that showed a tied race, 45 percent to 45 percent.

7.

North Carolina

Ted Budd (R) vs. Cheri Beasley (D)POLITICO Election Forecast rating: Lean RepublicanRCP polling average: Budd +4.5 (Last week: Budd +2.8)2020 RCP polling average 10 days before the election: Biden +1.5Eventual margin: Trump +1.3

A Marist College poll out this week showed GOP Rep. Ted Budd and Democrat Cheri Beasley tied among all registered voters — but Budd with a 4-point lead among those who say they will "definitely" vote next month.

Undecideds accounted for 1-in-10 of the registered-voter sample, but only 5 percent of definite voters said they hadn't made up their minds yet.

8.

Ohio

J.D. Vance (R) vs. Tim Ryan (D)POLITICO Election Forecast rating: Lean RepublicanRCP polling average: Vance +2.2 (Last week: Vance +2.3)2020 RCP polling average 10 days before the election: Trump +0.6Eventual margin: Trump +8.2

Ohio is one of only two of the core 10 states where the GOP candidate didn't increase his lead over the past week (yes, all 10 Republican nominees are men).

That's mostly driven by two public polls out on Monday, one from Marist College and the other from Siena College for Spectrum News, showing a tied race.

Meanwhile, the Republican firm Cygnal continues to show GOP nominee J.D. Vance leading Democratic Rep. Tim Ryan in its tracking poll, with the latest version staking Vance to a 5-point lead.

9.

Pennsylvania

Mehmet Oz (R) vs, John Fetterman (D)POLITICO Election Forecast rating: Toss UpRCP polling average: Fetterman +0.3 (Last week: Fetterman +2.4)2020 RCP polling average 10 days before the election: Biden +5.3Eventual margin: Biden +1.2

We're still waiting for more data following Tuesday night's big debate between Democrat John Fetterman and Republican Mehmet Oz. The only survey to qualify for the RealClearPolitics average was a one-day poll from the GOP firm InsiderAdvantage, showing Oz narrowly ahead. But polls conducted in a single day are generally less reliable because they only capture the easiest-to-reach respondents.

10.

Wisconsin

RON JOHNSON (R) vs. Mandela BarnesPOLITICO Election Forecast rating: Toss UpRCP polling average: Johnson +3.3 (Last week: Johnson +2.8)2020 RCP polling average 10 days before the election: Biden +5.4Eventual margin: Biden +0.7

Two new polls this week had the same leader — GOP Sen. Ron Johnson — but portrayed slightly different pictures of the race's competitiveness. A Data for Progress poll showed Johnson leading Democrat Mandela Barnes by 5 points, 51 percent to 46 percent.

But a CNN poll also out this week showed Johnson ahead by a single point, 50 percent to 49 percent. Both showed few voters are left undecided in the sharply polarized state.