He also gained support after refusing to deploy the military to crack down on massive anti-Syrian street demonstrations in March 2005, days after the assassination of Rafiq al-Hariri, the former prime minister.
'Call of duty'
Suleiman, who holds a Bachelor of Arts degree in political and administrative sciences from Lebanese University, has said his 56,000-strong army should ignore politics "and listen to the call of duty".
|Lebanon's army defeated fighters at Nahr |
al-Bared refugee camp after a long siege [AFP]
"The state exists because the army is the guardian of the structure of this state," he has said.
His profile as a strong Lebanese leader was boosted after the Lebanese army cleared the Nahr al-Bared Palestinian refugee camp of al-Qaeda-inspired Fatah al-Islam fighters after a 15-week siege earlier this year.
Under his command, the army also calmed sectarian violence and deployed in strongholds of Hezbollah.
The Lebanese public view the army as the country's most effective state organ.
The army is currently working alongside a multi-national UN force in southern Lebanon, acting as a buffer between Hezbollah and Israel, who fought each other in 2006.
Since al-Hariri's assassination in February 2005, Lebanon has seen increased sectarian tensions.
Sunni Muslims in Lebanon largely support Siniora's majority bloc in parliament while most Shia Muslims support the Hezbollah-led opposition.
Suleiman has distanced himself from Hezbollah, which once co-operated closely with the military, but critics accuse him of not doing enough to stop weapons smuggling to Hezbollah from Syria.
During the 34-day war between Hezbollah and Israel in 2006, the Lebanese military stood back.
According to Lebanon's constitution, senior public servants can seek the presidency only two years after resigning from their current post.
The Future Movement, a major party within the ruling coalition, has accepted a change to the constitution to break the impasse over a consensus president.
Suleiman, who graduated from Lebanon's military academy as second lieutenant in 1970, would have to retire from the mlitary in order to become the elected president of Lebanon's 127-member parliament.