Rep. Martha McSally is getting some help from two big Republican names in her bid to replace the retiring Sen. Jeff Flake: former President George W. Bush and 2012 GOP presidential nominee Mitt Romney.

Just weeks ahead of the Nov. 6 election, Bush and Romney separately will swing through the Valley to raise money for McSally and rally Republicans in support of the two-term GOP congresswoman from Tucson.

With her race against Democratic Rep. Kyrsten Sinema for the open Senate nearly a dead heat, McSally is leaning on Bush and Romney to widen her appeal with more moderate Republicans as well as East Valley women and Mormons, whose support is crucial to winning.

McSally has embraced President Donald Trump, who wields tremendous influence with the GOP base, but whose rhetoric and policies have alienated more moderate Republicans and GOP-leaning independent voters.

Romney, who is Mormon and is running for the U.S. Senate in Utah, will headline a rally for McSally on Friday in the East Valley, which has a significant Mormon population. The event is scheduled for 2:30 p.m. at the Falls Event Center in Gilbert.

On Oct. 19, Bush is hosting a private fundraising breakfast in Scottsdale.

That event is led by automotive mogul and GOP donor Jim Click and Carolyn and Craig Jackson, of the classic car auction empire. Breakfast with the former president is $2,700 a person and photos are $5,000 a pop.

Trump is expected to visit later this month to fire up GOP voters ahead of the election. It is unclear how his appearance would ultimately play: slightly more Arizona voters disapprove of him than approve of him, the newspaper's poll of 500 registered Arizona voters shows.

Arizona’s race for the open U.S. Senate seat is one of the nation’s most competitive. Political analysts have rated it a toss-up, meaning no candidate has a clear advantage.

Sinema has represented a Phoenix-area district for three terms and is a former social worker, state lawmaker and attorney.

RELATED: Senate race: Why Martha McSally and Kyrsten Sinema seem so scripted

A recent Suffolk University/Arizona Republic poll shows McSally trailing among likely voters by three points behind Sinema, with 44.6 percent. But many voters still had not decided whom they will support in the general election. The results fell within the poll’s margin of error of plus-or-minus 4.4 percentage points.

The poll also shows Sinema with an advantage among independent voters.

Torunn Sinclair, McSally's campaign spokeswoman, said the campaign wants Arizonans of all political persuasions to support McSally.

“We are working hard to rally support from across the Republican Party, Independents, and Democrats that are tired of candidates like Kyrsten Sinema who talk independent, but vote liberal," she said.

Sinema’s voting record, as tracked by the website FiveThirtyEight, shows Sinema voting in line with Trump’s position 62 percent of time. Sinema has run her campaign as an independent-minded Democrat who works across party lines.

Sinema’s endorsements include former President Barack Obama and former Arizona Attorney General Grant Woods.

The Suffolk University/Arizona Republic poll also shows that more Arizonans view McSally as unfavorable than favorable; Sinema is viewed more favorably than not.

Follow the reporter on Twitter and Facebook. Contact her at yvonne.wingett@arizonarepublic.com.

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