The United States stands ready to engage Iran in "serious dialogue," President Barack Obama reiterated in Dresden last Friday. Formal talks - on bilateral relations and halting Teheran's quest for nuclear arms - await the outcome of today's Iranian presidential election. Obama indicated that there would be a "serious process of engagement, first through the P5-plus-one process" (meaning the permanent members of the UN Security Council plus Germany) and "potentially through additional direct talks between the United States and Iran." If these talks prove unsatisfactory after six months or so, Washington could then, in conjunction with the P5-plus-one, seek to ratchet up economic sanctions against the Islamic republic. While this glacially-slow scenario stretches out, the centrifuges will spin and multiply. Iran's drive for atomic weapons and the means to deliver them will appear ever more inexorable. But what if Obama's softer tone encourages Iranian voters to walk away from Mahmoud Ahmadinejad, on the grounds that his braying has become superfluous and the American "threat" has diminished? And wouldn't our region be a better place if the demagogic Ahmadinejad was replaced by the reformist Mir Hossein Mousavi? Perhaps. But likely not. First off, the real authority in Iran, the figure who sits above all levers of power, is Ayatollah Ali Khamenei. The president is subservient to him. One sure sign that a US-Iranian dialogue was being taken seriously in Teheran would be the extent to which Khamenei himself was engaged. All too helpfully for the mullahs, an Ahmadinejad defeat would distance the regime from the odious Holocaust-denier. A Mousavi victory would provide it with a human face, making it even less likely that the P5-plus-one would stop the mullahs from building a bomb. All the candidates - Ahmadinejad, Mousavi, and dark-horse challengers Mahdi Karoubi and Mohsen Rezaei - concur that Iran's nuclear program, which they insist is for peaceful civilian purposes, must remain inviolate. All are willing to improve relations with the US in return for fundamental "changes" in American policy. None can be expected to downgrade Iran's proxy relationship with Hizbullah, or its support of Palestinian Islamists. Domestically, Mousavi and Karoubi oppose the coercive approach Ahmadinejad's supporters take regarding Islamic dress and social behavior. The president's opponents also say that the economy should be doing a lot better considering that Iran has the world's second-biggest oil and gas reserves. Inflation is high, between 14 and 24 percent, depending on how the numbers are massaged. Unemployment stands at 17%, particularly significant in a country where half the population is 27 years old or younger. Ahmadinejad is leading in the polls thanks to support from the downtrodden masses, whose lives he has dramatically improved by raising salaries and benefits. Mousavi's supporters are more urbane. They want to see investment that fosters long-term economic growth. ALL THE trappings of democracy are on display: elections, candidate debates, mass rallies - even mudslinging. For the regime's Western apologists, this proves that while Iranian democracy may be "incomplete" (since only candidates vetted by Khamenei are eligible to run), the country is far from being the totalitarian ogre that Zionist "demonizers" claim. Admittedly, we find it difficult to keep an open mind with the Supreme Leader constantly denouncing Israel as a "cancerous growth," as he did on the same day Obama spoke in Cairo. We've noted, too, that his Revolutionary Guard warned that once the election is decided - no more mass ralliesâ€¦ or else. Speaking of mudslinging, Ali Akbar Rafsanjani and Ahmadinejad have been doing lots of it. Rafsanjani, a former president, is one of the most well-connected and richest men in Iran. He sits on the Council of Experts, which has the theoretical power to remove Khamenei himself. Rafsanjani wrote the Supreme Leader to complain about Ahmadinejad saying Rafsanjani had enriched himself during his presidency. Ahmadinejad is angry because Rafsanjani's organization is backing Mousavi's campaign. Rafsanjani-commissioned polls show Mousavi with a 56-42 lead. To ensure the election isn't stolen, Rafsanjani's forces are fielding 50,000 poll-watchers. International monitors are barred. The election results will be known tomorrow. But no matter the outcome, the international community needs a timely way to get the Supreme Leader's attention - or the big losers will continue to be the Iranian people and their neighbors in the region.