Sen. John McCain's leading opponent in last year's Republican Senate primary says the cancer-stricken senator should resign "as quickly as possible" and Arizona's governor should think about naming her to replace him.

Former State Sen. Kelli Ward, who's running against Republican Sen. Jeff Flake in next year's primary, told an Indiana radio station Thursday:

"I hope that Senator McCain is going to look long and hard at this, that his family and his advisers are going to look at this, and they're going to advise him to step away as quickly as possible, so that the business of the country and the business of Arizona being represented at the federal level can move forward."

Ward, who is a family doctor in Lake Havasu City, made the comments the day after doctors revealed the 80-year-old McCain had been diagnosed with an aggressive form of brain cancer.

"As a Christian I know there can always be miracles," Ward said.

"But the likelihood that John McCain is going to come back to the Senate and be at full force for the people of our state and the people of the United States is low."

Under Arizona law, if McCain resigned, Gov. Doug Ducey would have to name a replacement from the same party. A special election for McCain's seat would then be held in November 2018.

When asked if she wanted to be considered as a McCain replacement, Ward said: "I certainly hope so... I made an extremely good showing against Sen. McCain, against all odds... I am beating the pants off Jeff Flake already."

McCain won his 2016 Republican primary with 51.2 percent of the vote in a four-person field. Ward finished second, with 40 percent of the vote.

The Ward campaign provided a poll Thursday showing she leads Flake, 48 percent to 31 percent, among registered Republicans who voted in the GOP presidential and Senate primaries in 2016 and who are likely to vote in the 2018 primary.

Ward's latest campaign finance report, for the first six months of this year, shows she is spending money as fast as she takes it in. She raised about $360,000 but spent $352,000. The Ward campaign reported $84,000 cash on hand plus debts of $137,000.

Flake campaign manager Josh Daniels said of the Ward poll: “Kelli Ward is having a very bad press day. Fake poll numbers won’t change that.”

Flake issued this statement: "John McCain is a fighter and an American hero. I fully expect to see him back in the Senate soon. I’m dumbstruck by Kelli Ward’s comments.”

McCain's staff declined to comment.

Ward said the potential loss of McCain's vote in the Senate while he underwent treatment could hurt the Republican agenda.

"We can't be at a standstill while we wait for John McCain to determine what he's going to do," Ward said.

Ward tweeted this message after McCain's diagnosis was made public:

Earlier this week, the Ward campaign canceled a scheduled joint appearance and an "intimate dinner" next week in Scottsdale with Roger Stone, a Trump aide and political provocateur. Stone had claimed in a Phoenix radio interview Tuesday that McCain was "mentally ill... He's a nut case."

A Ward spokeswoman told The Yellow Sheet that the cancellation was the result of a scheduling conflict.

Stone is still set to speak to Pima County Republicans next week.