Opposition parties and analysts say such a move would be resisted at all cost.
Grace told thousands of Zanu PF party supporters in Murewa last week that Mugabe would continue to rule even from a wheelchair, or if he got blind.
“I said we will make a special wheelchair for Mugabe such that when he can’t walk, we will push him to rallies,” she said.
“We have travelled a lot [around the world] and we have seen that happening. Other leaders are blind and if Mugabe turns blind, who cares, he is our choice.”
Mugabe is struggling with old age and ill-health and has been captured on several occasions struggling to walk, amplifying calls from the opposition for the 91- year-old veteran leader to step down.
But Zanu PF provinces have already endorsed him as their sole 2018 presidential candidate when he will be 94 to serve another five-year term that will see him ruling until 2023 when he would be 99.
MDC spokesperson, Kurauone Chihwayi said Zimbabweans will resist a “home-based care” leader.
“Zimbabweans, including politically blind Zanu PF supporters, will never allow Mugabe to rule from a wheelchair,” said Chihwayi.
MDC-T spokesperson Obert Gutu said the wheelchair statement was a crude insult to the people.
“The infamous wheelchair statement is a gross and crude insult to all right-thinking and patriotic Zimbabweans,” he said.
“She thinks we are trash. This woman will very soon be surprised by the resilience as well as the brilliance of Zimbabweans.”
Political analyst Takura Zhangazha said Grace’s statement showed a “semblance of desperation.”
“I think the statement was made in a ‘populist moment’ in order to demonstrate that anyone harbouring ambitions to succeed her husband is involved in an exercise in futility,” Zhangazha said.
“It, however, has a double meaning, that of a semblance of desperation to make the point that her husband is not leaving office anytime soon, indicating that indeed there are those that harbour those said ambitions.”
Another commentator, commenting on social media identifying himself as Mokwena, said it was now evident a Zanu PF faction was desperate to block Vice-President Emmerson Mnangagwa from succeeding Mugabe.
“It clearly underlines the thinking behind G40 that the longer Mugabe stays, the slimmer are the chances for Mnangagwa, who by the time Mugabe gets to 100 as per his wife’s wish, will be above 80 years,” he wrote.
Zimbabwe Civic Education Trust executive director Gladys Hlatywayo said there was an “obvious futile attempt to defy the force of nature” by those trying to prolong Mugabe’s rule.
“Ageing is a natural process that every person goes through. When someone is ageing, faculties start to deteriorate and they are advised to rest. It is evil and insensitive to encourage old people to perform duties meant for the young and energetic,” Hlatywayo said.