Dan Nowicki

The Republic | azcentral.com

First lady Michelle Obama will campaign Thursday in Phoenix, becoming the third major Hillary Clinton surrogate to visit Arizona in as many days.

Arizona is a traditional red state, but polls have shown Clinton unexpectedly competitive here against Republican presidential nominee Donald Trump. Former President Bill Clinton is the last Democrat to carry the state, in 1996.

The campaign announced that Obama will speak at the Phoenix Convention Center from 2 to 3 p.m. Thursday. Doors are scheduled to open at 11:30 a.m.

READ OUR LIVE BLOG:First lady Michelle Obama in Phoenix

The Clinton campaign asked attendees to RSVP and promised Tuesday to "be in touch with details soon."

Like Sen. Bernie Sanders in Flagstaff and Tucson on Tuesday and Chelsea Clinton in Tempe on Wednesday, Obama will appear at an Arizona Democratic Party get-out-the-vote rally on Thursday.

The three surrogates raise speculation that the Clinton campaign sees Arizona as truly in play and makes an appearance by Hillary Clinton herself more likely. Bill Clinton made a campaign stop at Arizona State University late in the campaign season the year he won Arizona. He spoke outside Gammage Auditorium on Oct. 31, 1996.

National Republicans on Monday pushed back against the idea that Clinton can carry Arizona.

“Arizona has been a Republican stronghold for nearly half a century, electing strong, conservative leaders up and down the ballot," said Natalie Strom, a Republican National Committee spokeswoman. "Democrats have tried and failed before to turn Arizona blue, and they will fail again. The Clinton campaign is merely wasting resources in an effort to distract from their dishonest and untrustworthy candidate."

Hillary Clinton earlier this year appeared at Carl Hayden Community High School in Phoenix ahead of her victory in Arizona's March 22 Democratic presidential-preference election.

Nowicki is The Arizona Republic's national political reporter. Follow him on Twitter at @dannowicki and on his official Facebook page.

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