All eyes are on whether presidential candidates will unite for one-to-one rivalry against Moon Jae-in of the Democratic Party of Korea.

Now that party nominations are over and as competition among nominees has just started, a coalition or single candidacy looks unlikely at present.

To begin with, uniting the Bareun Party and the Liberty Korea Party would not be easy, as the two conservative parties are far from integration. They are battling hard for leadership in traditionally conservative electorates in southeastern provinces.

The Bareun Party says it will not discuss uniting with the Liberty Korea Party unless it expels hardcore loyalists of former President Park Geun-hye.

On the other hand, the Liberty Korea Party is delaying their expulsion on the basis that Park has been impeached and jailed. It is just calling for the reintegration of conservative forces under its wing.

Two underdog candidates, Hong Joon-pyo of the Liberty Korea Party and Yoo Seong-min of the Bareun Party, are clashing with each other.

Hong has called the Bareun Party “a runaway” and asked its members to “stop acting like babies” and “come back home.” Yoo has called Hong “an unqualified, shameful candidate,” refusing to unite with the Liberty Korea Party.

With the two conservative candidates fighting each other, Ahn Cheol-soo of the People’s Party, favored by centrists, cannot but feel uncomfortable at the idea of joining hands with the Bareun Party, not to mention the Liberty Korea Party.

However, there is cause for unity against Moon. One pressing reason is that unless conservative and centrist candidates unite for a one-on-one fight against Moon, all of them are almost certain to lose, if polls so far are any guide.

In particular, the scenario of Ahn vying with Moon looks like a definite reason for anti-Moon voters to call for a single candidate.

A recent poll shows Ahn leading Moon 46.3 percent to 36.4 percent in such a scenario. But if all five nominees contest the race, Moon is likely to win.

Given the escalating war of words between Hong and Yoo, their alliance or the integration of their parties looks out of the question.

A coalition between Yoo and Ahn’s parties is also a long shot for now. Yoo has slammed the People’s Party platform against the deployment of a US anti-missile system. Ahn has vowed to defeat Moon on his own, ignoring the option of a coalition or a single candidate. But he may reconsider if his prospects don’t improve.

A one-to-one fight may not be an issue at all if Moon’s ratings decline. He may lose voters over alleged irregularities involving the employment of his son by the Korea Employment Information Service, worried over North Korean provocations and attacks over his views on national security.

In light of poll arithmetic, an anti-Moon alliance or single candidacy looks a sure way for Ahn to take power, but he should not overlook its risks.

Voters might be repulsed by a collusive alliance. It is risky to unite just to fight off a certain candidate.

Even if a candidate wins through a rushed alliance or agreement on a single candidate, conflicts within the coalition would likely erupt after the election.

If candidates want to unite, they should find common ground and try to accommodate their differences. They should share values for a new era and promise to push for reforms that the people want with nonpartisanship.

Attempts to unify candidates to take power without converging their policies and visions would be nothing more than political collusion that goes against the times and public sentiment.

A one-to-one contest looks a far off prospect, for now at least.