Democratic challenger leads in Arizona Senate race: Reuters/Ipsos

By Jason Lange

WASHINGTON (Reuters) - Democratic Senate candidate Mark Kelly leads Arizona's Republican incumbent Martha McSally among likely voters, according to Reuters/Ipsos opinion polls released on Wednesday.

There are about nine competitive U.S. Senate races this year, seven with vulnerable Republican incumbents and two with vulnerable Democrats. To win the Senate, Democrats need to pick up three seats if the party wins the White House and four if not.

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

ARIZONA

* 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

MICHIGAN

* 49% of likely voters polled from Sept. 11 to 16 said they planned to vote for incumbent Democrat Gary Peters.

* 43% planned to vote for Republican challenger and businessman John James, with the remaining voters undecided or planning to vote for another candidate.

* 2% said they had already voted.

NORTH CAROLINA

* 48% of likely voters polled Sept. 11 to 16 said they planned to vote for the Democratic challenger, former state Senator Cal Cunningham.

* 44% planned to vote for incumbent Republican Thom Tillis, with the remaining voters undecided or planning to vote for another candidate. Cunningham's 4-point lead is within the poll's credibility interval, making the race in essence a toss-up.

* 4% said they had already voted.

NOTES: The Reuters/Ipsos poll was conducted online and in English. The Michigan poll surveyed 637 likely voters and had a credibility interval of 4 percentage points. North Carolina's surveyed 586 likely voters and had a credibility interval of 5 percentage points. Arizona's surveyed 565 likely voters and had a credibility interval of 5 percentage points

(Reporting by Jason Lange; editing by Jonathan Oatis)