Democrat Cunningham appears to lead Republican Tillis in North Carolina: Reuters/Ipsos poll

Poll workers prepare absentee ballots for the general election in Raleigh

By Jason Lange

WASHINGTON (Reuters) - Democratic Senate challenger Cal Cunningham appears to lead incumbent Senator Thom Tillis in North Carolina, according to a Reuters/Ipsos poll taken as the news broke of Tillis' COVID-19 diagnosis and a scandal involving Cunningham.

Democratic Senator Gary Peters of Michigan leads his Republican challenger businessman John James among likely voters, according to the opinion polls released on Tuesday.

There are about ten competitive U.S. Senate races this year, eight with vulnerable Republican incumbents and two with vulnerable Democrats. To have a majority in the Senate, Democrats need to pick up three seats if the party wins the White House, which gives the vice president a tie-breaking vote, and four if not.

Here are the latest results on three Senate races on which Reuters/Ipsos is polling:

NORTH CAROLINA

* 47% of likely voters polled Sept. 29 to Oct. 6 said they planned to vote for the Democratic challenger, former state Senator Cunningham. Cunningham last week issued a public apology after sending sexually themed text messages to a woman who is not his wife.

* 42% planned to vote for Tillis, with the remaining voters undecided or planning to vote for another candidate. Tillis has tested positive for the coronavirus, and said he would isolate at home for 10 days. The number of undecided voters had risen slightly for the last poll two weeks ago.

* 8% said they had already voted.

MICHIGAN

* 50% of likely voters polled from Sept. 29 to Oct. 6 said they planned to vote for incumbent Peters.

* 43% planned to vote for James, with the remaining voters undecided or planning to vote for another candidate.

* 10% said they had already voted.

ARIZONA (SEPT. 11-17 POLL)

* 50% plan to vote for the Democratic challenger, former astronaut Mike Kelly.

* 41% of likely voters polled Sept. 11 to 17 say they plan to vote for incumbent Republican Martha McSally, with the remaining voters undecided or planning to vote for another candidate.

* 3% say they have already voted.

NOTES: The Reuters/Ipsos poll was conducted online and in English. The Michigan poll surveyed 709 likely voters and had a credibility interval of 4 percentage points. North Carolina's surveyed 693 likely voters and had a credibility interval of 4 percentage points. The earlier Arizona survey included 565 likely voters and had a credibility interval of 5 percentage points.

(Reporting by Jason Lange; Editing by Sonya Hepinstall)