This is the first time in Pakistan's history that an elected civilian government has completed a full five-year term and will be replaced democratically.
At this stage, the only likely outcome is continued Pakistan Peoples Party control of the Senate and its 104 seats as only one-third of the senators are up for re-election.
Most polls rank Nawaz Sharif and his Pakistan Muslin League (N) party as the favorite possibly winning 90-100 out of 342 seats in Parliament, far short of a majority.
Zardari's PPP, led by his son Bilawal, and Cricket hero Imran Khan's Pakistan Tehreek-e-Insaf will most likely vie for second or third place. A host of smaller parties will win handfuls of seats.
Voter turnout in the last election in 2008 was about 55 percent. Whether larger numbers of women and youthful voters will swell the ranks is unclear. Conventional wisdom suggests that a surge helps Imran's PTI. However, conventional wisdom in Pakistan is often an oxymoron.
Meanwhile, the Tehrik-iTaliban Pakistan and other militant groups are disrupting the elections killing off candidates largely from PPP and Awami National Party lists.
A few analysts suggest that given the devolution of power to the four provinces, provincial elections may prove more important than the national vote. However, the geostrategic challenges of the region and Afghanistan in particular are so great that while this theory might relate to domestic economic issues, the next government in Islamabad will be crucial in shaping South Asia's security for good or for ill.
Presidential elections are schedules for later in the year. The four provincial assemblies and the two houses of the national government, not popular votes, will decide whether Zardari stays or goes. And recently returned former President Pervez Musharraf is a non-issue currently under house arrest.
Those wanting PPP to go contend that PML-N will win the largest plurality and form a coalition government intent on fixing the myriad economic and social issues threatening Pakistani well-being. The presumption is that Nawaz has learned from his two failed premierships and succeeding what is viewed as a largely unsuccessful PPP government, ultimately will win public support.
But many don't see Nawaz as either reformed or as a reformer. Much as PPP was forced by coalition politics to bring minority parties into a huge and largely dysfunctional cabinet, so too will PML-N face similar realities.
Many also distrust Nawaz's anti-Americanism and pro-Saudi position that could too easily succumb to religious fundamentalist influence, much as did Gen. Zia al-Haq's rule of nearly 30 years ago veered, Pakistan in that unfortunate direction.
Regardless, the army almost certainly will stay out of politics. Selecting the next army chief of staff to replace Gen. Ashraf Kayani, already twice extended, will go smoothly. Several highly qualified candidates are in play including for the post of chairman of the Joint Chiefs, a position less important in Pakistan than in other countries.
One key question is how the election will affect the Zardari-Nawaz relationship. The presidency is a weak and largely ceremonial office. Zardari maintains power through control of the party.
If PPP loses the Assembly, obviously Zardari will likewise lose authority. However, Nawaz may need PPP to form a coalition government. Under those circumstances, who knows what sort of deal may transpire. After all, Zardari went out of his way in 2008 to bring Nawaz and PML-N into government.
But it is the perils and paradoxes of Pakistani politics that hold greater sway. PTI could make a surprisingly stronger showing. While the religious parties have attracted very minor electoral representation, that might change. And the strength of various PPP candidates could indeed produce a long-shot victory.
The United States has taken an understandably hands off approach. Privately, it views the current government as weak and lacking in competence, preferring to deal with the army. And some in the U.S. State Department say Nawaz would make a better partner.
They are wrong. If the United States wasn't happy with PPP, a PML-N coalition won't prove better.
A hung Parliament is also possible. Under the Constitution, the president can set a deadline for establishing a government. But would that work? As the U.S. Congress seems incapable of governing if the sequester and budget are illustrative, why would Pakistan fare better?
Governance is thus crucial. Given the immense challenges and dangers facing Pakistan from worsening insurgencies to growing economic woes, no matter who is elected, will that team be able to govern with any degree of success? Pakistan is about to find out.
(Harlan Ullman is chairman of the Killowen Group, which advises leaders of government and business, and senior adviser at Washington's Atlantic Council.)
(United Press International's "Outside View" commentaries are written by outside contributors who specialize in a variety of important issues. The views expressed do not necessarily reflect those of United Press International. In the interests of creating an open forum, original submissions are invited.)