Welcome to Pollapalooza, our weekly polling roundup.

Poll of the week

Holding onto all of their U.S. Senate seats in red states would all be for naught for Democrats if they don’t net the two pickups they need to take control of the chamber. This week, two polls came out showing that Democrats are comfortably ahead in one must-win state — Arizona, where Republican Sen. Jeff Flake is retiring.

But there’s reason to think that cushion won’t hold up to the rigors of the general election.

According to a CBS News/YouGov poll conducted June 19-22, likely Democratic nominee U.S. Rep. Kyrsten Sinema leads all of her potential Republican opponents by at least 7 percentage points among registered voters: She leads Rep. Martha McSally 41 percent to 34 percent, former state Sen. Kelli Ward 43 percent to 35 percent and former Maricopa County Sheriff Joe Arpaio 45 percent to 28 percent. An NBC News/Marist poll conducted June 17-21 showed similar results: Sinema led McSally 49 percent to 38 percent, Ward 48 percent to 38 percent and Arpaio 57 percent to 32 percent.

If we take these results at face value, Arizona doesn’t even look that competitive; Sinema would be heavily favored. But there’s plenty of reason to believe that the race will tighten before November. One red flag is the high number of respondents who refused to support one of the two major party candidates. Instead, from 11 percent to 27 percent of voters said that they were undecided, intended to vote for a third-party candidate or won’t vote at all.

This week’s polls of the Arizona U.S. Senate race Poll Dem GOP Someone else/other Not sure/ undecided Wouldn’t vote Total uncommitted Sinema vs. Arpaio (YouGov) 45% 28% 13% 11% 3% 27% Sinema vs. McSally (YouGov) 41 34 8 14 2 24 Sinema vs. Ward (YouGov) 43 35 7 14 1 22 Sinema vs. Ward (Marist) 48 38 2 12 N/A 14 Sinema vs. McSally (Marist) 49 38 2 11 N/A 13 Sinema vs. Arpaio (Marist) 57 32 2 9 N/A 11 Sources: CBS News/YouGov, NBC News/Marist

But many of these voters won’t stay uncommitted. Undecided ones will hop off the fence, and lots of people who now say they’ll support a third-party candidate probably won’t follow through with it. (Third-party support tends to decline as campaigns progress.)

The large share of uncommitted voters adds a layer of uncertainty to the race. Remember, we saw the same thing in 2016; Hillary Clinton had a small lead over Donald Trump heading into Election Day, but the unusually high number of undecided voters helped Trump squeak out an Electoral College win.

The uncommitted bloc looks likely to help the GOP in Arizona too. According to the crosstabs of these polls, these Arizonans are disproportionately Republican. For example, in the YouGov poll pitting Sinema against Ward, 92 percent of self-identified Democrats back Sinema, 4 percent aren’t sure and 1 percent want to vote for someone else — but among self-identified Republicans, just 75 percent support Ward, 11 percent aren’t sure and 8 percent say they’ll vote for someone else. In Marist’s Sinema-McSally matchup, 88 percent of Democrats are behind Sinema and just 2 percent are undecided; just 77 percent of Republicans support McSally and 13 percent say they’re undecided.

Why the disparity? Republicans are in the midst of a contentious primary between McSally, Ward and Arpaio, while Democrats are united behind Sinema. Many Ward voters, for example, are not inclined to think kindly of McSally at the moment, and that’s probably keeping some usually reliable Republican voters from telling pollsters they will support the party’s nominee no matter what. But by the fall, these voters usually return to the fold as hard feelings from the primary fade away.

These voters alone probably aren’t enough to erase a lead as big as the one Sinema has, but Republicans haven’t yet begun attacking her in earnest; when they set their sights on her after the primary, her favorability with independents (a subgroup she is winning in all three matchups in both polls) probably will drop. But so far, with mud flying on only one side of the ledger, it hasn’t been a fair fight.

I’m not saying Sinema can’t win (let’s not get too cute; these polling numbers are great news for her), but I am saying Democrats would be foolish to take Arizona for granted or divert resources from it on the basis of a few early polls. Demographics make Democrats’ path to victory in the Grand Canyon State a narrow one: Despite a growing minority (especially Latino) population, it is not yet a big enough share of the electorate to hand Democrats a win on their own. Sinema could still win by performing respectably among white voters, which she does in the polls from this week. That’s possible because Sinema has forged one of the most conservative voting records of any House Democrat and Arizona is a fairly elastic state, meaning its voters are generally persuadable. But at the end of the day, it is still discernibly red — 7 percentage points further right than the nation as a whole, according to FiveThirtyEight’s partisan lean metric. Once Arizona’s base partisanship sets in and currently uncommitted voters come home to their usual camps, this is likely to be every bit the toss-up race everyone thinks it will be.

Other polling nuggets

64 percent of Americans said they are not at all interested in the FIFA World Cup, and 69 percent said they do not intend to watch any matches, according to a recent YouGov poll.

In light of Sarah Huckabee Sanders being told to leave a restaurant because she worked for President Trump, a Harvard-Harris Poll asked if it is acceptable to discriminate against people in public restaurants for their political views; 28 percent said it was acceptable, while 72 percent (including 60 percent of Democrats and 80 percent of Republicans) said it was not.

The Harvard-Harris poll also asked Republican voters why they support their party. Sixty-nine percent said it was more because they support the policies of Trump and Republican candidates, while 31 percent said it was more because they oppose the policies of the Democratic Party and its candidates.

A Gallup Poll found that 75 percent of Americans say immigration is a good thing for the country. That number includes 65 percent of Republicans and 85 percent of Democrats and is the highest Gallup has found since it started asking the question in 2001.

According to a Rasmussen poll, 40 percent of Americans oppose the creation of a “space force” as the sixth branch of the military. Thirty-three percent favor it, and 27 percent are not sure.

A majority of Americans keep their cellphones on or directly next to their beds when they sleep, according to a YouGov survey.

23 percent of Americans have no money saved for emergencies, according to a survey by SSRS.

Americans have some pretty big misperceptions about the makeup of the two major political parties, according to a new study released in the Journal of Politics. Democrats for example, estimate that 44 percent of Republicans earn over $250,000 per year. In reality, only 2 percent do. Our colleague Perry Bacon Jr. wrote more about the study and its implication.

Mexico hosts a federal election on Sunday to choose a new president and congress. According to the last public polls conducted prior to the blackout period (during which publishing polls is banned), the left-wing populist Andres Manuel Lopez Obrador is the front-runner. He leads the competition by nearly 26 points, according to an average of polls taken by Bloomberg.

Trump approval

According to FiveThirtyEight’s tracker, Trump’s approval rating sits at 41.9 percent; his disapproval is 52.3 percent. That -10.4-point spread is a tad wider than the -9.2-point spread from one week ago, perhaps indicating that last week’s immigration controversy has taken its toll. However, it’s close to the 10.1-point gap (42.4 percent approval, 52.5 disapproval) from this time last month.

Generic ballot

According to FiveThirtyEight’s model of the generic congressional ballot, Democrats are winning the race for Congress 46.5 percent to 40.1 percent over Republicans. That 6.4-point lead is little changed from their 6.3-point advantage (46.9 percent to 40.7 percent) from last week and just a skosh higher than their 5.9-point lead (45.6 percent to 39.7 percent) one month ago today. As a reminder, experts believe Democrats need to win the House popular vote by around 7 percentage points to flip the chamber.