Florida Senate race is close, while Democrats hold solid leads in Arizona and Ohio, polls say

Tom Williams | CQ-Roll Call | Getty Images

Rep. Kyrsten Sinema, D-Ariz. 

The likely Democratic nominee, U.S. Rep. Kyrsten Sinema, holds a double-digit lead over all of her potential opponents, according to an NBC/Marist poll. In a hypothetical contest with Rep. Martha McSally, Sinema gets 49 percent of support among registered voters, compared with 38 percent for the Republican candidate.

The Democratic representative has a 10-percentage point edge — 48 percent to 38 percent — over physician and former state legislator Kelli Ward. Sinema’s lead balloons to 25 percentage points — 57 percent to 32 percent — against former Maricopa County Sheriff Joe Arpaio.

The race for the GOP nomination appears tight ahead of the August 28 primary. McSally garners 30 percent of support among the potential Republican electorate, compared with 28 percent for Ward and 21 percent for Arpaio, according to the poll.

In Ohio, incumbent Democratic Sen. Sherrod Brown holds a comfortable lead in his race against GOP Rep. Jim Renacci. More than half of respondents, 51 percent, say they would prefer Brown, versus 38 percent for Renacci.

The NBC News/Marist poll of Arizona was conducted June 17-21 of 839 registered voters (which has a margin of error of plus-minus 4.5 percentage points) and 371 Republican primary voters (plus-minus 6.7 percentage points).

The NBC News/Marist poll of Florida was conducted June 17-21 of 947 registered voters (plus-minus 3.9 percentage points), 344 registered Democrats (plus-minus 6.5 percentage points) and 326 Republicans (plus-minus 6.7 percentage points).

The NBC News/Marist poll of Ohio was conducted June 17-22 of 778 registered voters (plus-minus 4.4 percentage points). All three live-caller polls interviewed respondents by landline and cell phone.