Sens. Mark Kelly of Arizona and Catherine Cortez Masto of Nevada.
CNN  — 

New CNN polling in two critical Senate battlegrounds finds that Arizona Democratic Sen. Mark Kelly holds a narrow lead over Republican challenger Blake Masters, while there is no clear leader in the race in Nevada between Democratic Sen. Catherine Cortez Masto and her GOP opponent, Adam Laxalt.

The Arizona poll finds that 51% of likely voters are behind Kelly, with 45% backing Masters. In Nevada, 48% of likely voters support Laxalt, with 46% behind Cortez Masto.

The polls suggest the underlying political climate in each state favors the GOP. Voters in both states are more likely to say the country will be better off than worse off if Republicans are in control of Congress (among registered voters, 44% to 35% in Nevada, 44% to 38% in Arizona), and President Joe Biden’s approval ratings break negative (39% approve and 60% disapprove in each state).

Republican voters in both Arizona and Nevada also express stronger motivation to turn out to vote (in each state, 62% of Republican registered voters say they are extremely motivated to vote versus 52% of Democrats).

Both races are crucial in the battle for control of the evenly divided Senate, where Democrats are defending a narrow majority held up by Vice President Kamala Harris’ tie-breaking vote. Arizona and Nevada have proved pivotal in recent election cycles. Both of the sitting Democratic senators won their seats by narrow, 2-point margins in presidential years, typically higher turnout contests than midterm elections.

Economic issues are the clear top concern for Arizonans and Nevadans, the polls found, with more than twice as many voters citing economy and inflation as their top issue as they did the second-place issue in each state, abortion (44% economy vs. 14% abortion in Nevada, 41% economy to 17% abortion in Arizona). Majorities in each state say that the economy there is worsening (63% in Arizona, 57% in Nevada), while a scant share in either state say things are improving (15% in Nevada, 6% in Arizona).

But neither Masters nor Laxalt, who were both endorsed by former President Donald Trump during their primaries, are viewed as favorably as the Democratic senators they are seeking to unseat – a factor that could work against them in the closing weeks of the campaign.

Other races

In both states, the closely watched gubernatorial contests are about evenly divided, with no clear leader in the race between Democrat Katie Hobbs and Republican Kari Lake in Arizona (49% of likely voters back Hobbs, 46% Lake), and a Nevada electorate similarly divided between Republican challenger Joe Lombardo and Democratic Gov. Steve Sisolak (48% back Lombardo and 46% Sisolak).

There are high-profile races for secretary of state in both states as well, with control of election administration in the upcoming 2024 presidential race at stake. Neither contest has a clear leader, however, with Arizona likely voters splitting 49% for Mark Finchem, the Republican, to 45% for Adrian Fontes, the Democrat, within the poll’s margin of error. In Nevada, 46% of likely voters back GOP nominee Jim Marchant with 43% behind Democrat Cisco Aguilar, also within that poll’s margin of error.

The Republican nominees in Arizona – Lake, Masters and Finchem – have drawn intense scrutiny because they were all endorsed by Trump after doggedly repeating his falsehoods about the 2020 election results in a narrowly divided state where he sought to overturn the results. Trump plans to campaign for all three nominees, along with election denier Abraham Hamadeh, the Republican nominee for state attorney general, on Sunday in Mesa, Arizona.

After the 2020 election, Arizona Republicans aligned with Trump pushed for a series of audits that ultimately led to the troubled sham review of the results in Maricopa County by the firm known as Cyber Ninjas.

Lake said during a primary debate that she would not have certified Biden’s victory in Arizona, repeatedly calling the election “stolen” and “corrupt.” Hobbs, Arizona’s Democratic secretary of state, has made Lake’s election denialism a central campaign plank and the subject of some of her fundraising appeals.

Finchem, a state lawmaker who has called for decertifying the results of the 2020 election, has argued for eliminating machine counting of ballots and he co-sponsored legislation in Arizona that would allow lawmakers to reject election results. His race has taken on outsize importance – not only because he would oversee elections in Arizona – but because the secretary of state position is second in line to the governorship in the Grand Canyon state.

Like Finchem, Marchant, the GOP secretary of state nominee in neighboring Nevada, has espoused baseless conspiracy theories about the 2020 election. Marchant told NBC News that he would not have certified Biden’s victory had he been Nevada’s secretary of state, even though Biden won the state with a 33,596 vote margin.

Laxalt, Nevada’s former state attorney general who co-chaired Trump’s Nevada campaign, was involved in the Trump campaign’s legal strategy challenging the 2020 result in the Silver State in state and federal courts. Those efforts failed.

The Trump and Biden factors

In Arizona, Masters’ connections to Trump appear to be a drag on his support. About half of Arizona voters (48%) say Masters is too supportive of Trump, while only 37% say his support for the former President is about right. By contrast, 47% say Kelly’s support for Biden is about right, while 43% consider him too supportive of the President.

In Nevada, views of Cortez Masto’s relationship to Biden are similar to Kelly’s: 46% say she is about right in her support for him, and 43% say she is too supportive. But Trump doesn’t appear to be quite as significant a factor for Laxalt. Nearly as many say his support for Trump is about right (39%) as say he is too supportive (44%).

Kelly holds a clear favorability advantage over Masters in Arizona: 49% of registered voters have a positive view of him vs. 32% for Masters. Nearly half, 48%, have an unfavorable opinion of Masters, while 39% say the same of Kelly. In Nevada, Cortez Masto’s favorability edge over Laxalt (45% hold a positive view of her, 35% of her opponent) appears offset by her own about equally large unfavorable rating (42% view Cortez Masto unfavorably, 46% say the same about Laxalt).

Voters who are focused on the economy and inflation break broadly for the Republicans in both states. In Nevada, 71% of likely voters who call the economy and inflation their top issue back Laxalt; in Arizona, it’s 61% behind Masters. Democrats hold a broad edge among the smaller pool focused on abortion (90% back Cortez Masto in Nevada, 84% Kelly in Arizona), and also among those who say their top issue is voting rights and election integrity (80% back Cortez Masto, 78% back Kelly).

Both Democrats hold wide leads among women. Men break broadly for Laxalt in Nevada (59% to 39%) but split about evenly in Arizona (47% Kelly to 49% Masters).

Independent likely voters are in Kelly’s corner in Arizona (53% Kelly to 38% Masters), while they break 47% for Laxalt to 42% for Cortez Masto in Nevada. Both Democrats carried more than 6 in 10 Latino voters in their previous winning bids for the Senate, but both lag among that group now. In Arizona, 57% of likely Latino voters support Kelly, compared with 65% who backed him in CNN’s 2020 Arizona exit poll. In Nevada, only about half of Latino voters support Cortez Masto (52% among registered voters, compared with the 61% she won according to 2016 exit polls). Cortez Masto is the first Latina to serve in the Senate.

About a quarter of registered voters in each Senate race say they either have not yet decided on a candidate or could change their minds before November (23% in Arizona, 26% in Nevada). And in both Senate contests, those persuadable voters are more likely to say they currently support the Democrat than the Republican running for Senate.

About 7 in 10 registered voters in each state express at least some confidence that votes cast in their state will be accurately cast and counted (70% in Arizona, 67% in Nevada), but the share who are deeply confident stands closer to 4 in 10 (38% in each state). There is a broad partisan divide, though, with only about half of Republicans confident in each state (54% in Arizona, 47% in Nevada) while 9 in 10 Democrats are confident in the vote count (90% in Nevada, 87% in Arizona).

The CNN polls in Arizona and Nevada were conducted September 26 to October 2 by SSRS, using a combination of online and telephone interviews. The survey samples were originally drawn from several sources and combined: probability-based online panel, registration-based sample and previously contacted random digit dial telephone numbers. Results among the full sample of 900 registered voters in Arizona have a margin of sampling error of plus or minus 4.4 percentage points; In Nevada, the full sample of 926 registered voters has an error margin of plus or minus 4.7 points. Likely voters were identified in each state through a series of questions about their intention to, interest in and past history of voting. Results among 795 likely voters in Arizona have an error margin of plus or minus 4.6 points; it is 5.0 points for the sample of 828 likely voters in Nevada.

CNN’s Maeve Reston and Ariel Edwards-Levy contributed to this report.