Sharif has openly questioned Pakistani-involvement in the American-led "war on terror."
But observers note he may adapt his approach if he becomes prime minister.
"He had good working relations with the United States in previous terms," Rizvi said. "My feeling is he will still have good relations. Once he gets into power, then he has to change."
For its part, the United States says it has no preferred contender in the elections.
"We do not support any particular political party or any individual candidate, and we look forward to engaging the next democratically elected government of Pakistan," Patrick Ventrell, a spokesman for the U.S. State Department, said last week.
A new approach to New Delhi?
Sharif has also raised eyebrows by vowing to improve ties with Pakistan's archrival, India. The two nuclear-armed neighbors have fought three wars since their partition at the end of British colonial rule.
One of those wars, in 1999, led to the military coup that drove Sharif out of office.
In a recent interview with the Indian broadcaster CNN-IBN, Sharif said he would carry out an investigation into the 2008 terrorist attacks in Mumbai, which killed more than 160 people.
India blames the Pakistan-based group, Lashkar-e-Tayyiba, for carrying out the attacks, accusing Islamabad of not doing enough to pursue its members. The group has denied responsibility.
If a new Pakistani government is successfully formed from the elections this weekend, it will be the first time in Pakistan's history that the country has democratically transitioned from one elected administration to another.
One of the reasons for that, analysts say, is that Sharif and his party took a pragmatic approach to being in opposition, despite their differences with the governing PPP and its leader, President Asif Ali Zardari, Bhutto's widower.
It's a far cry from the 1990s, when Sharif and Bhutto worked constantly to undermine each other's governments, resulting in instability and interference from the military.
The 21st-century Sharif, mindful of his overthrow and exile, appears more committed to upholding democratic, civilian government and not providing the military with an excuse to step in, according to Rumi.
"That by itself was a very promising development," he said.
The trouble with coalitions
The big question, however, is how effective any government that emerges from the elections will be.
Although several opinion polls have put Sharif's party in front, a great deal of uncertainty remains over how many seats it will end up with in the assembly.
Observers say there's a strong chance that both parties will fall short of an overall majority, resulting in a scramble to form a coalition with smaller parties.
The most prominent and potentially game-changing of the smaller parties is cricket-star-turned-politician Imran Khan's Pakistan Tehreek-e-Insaf (PTI), a new player in national elections.
Analysts are finding it hard to predict how many seats PTI candidates might secure, especially after Khan was seriously injured in a fall at a campaign rally this week.
If his party wins enough seats, the former captain of the Pakistani cricket team could find himself the kingmaker in its parliament.
But any coalition government may struggle to formulate strong policies on the critical issues Pakistan faces, even under an established figure like Sharif.
That could leave other institutions with room to exert their influence.