Since I moved to Beirut to continue my medical training, I've become able to see a more diverse people than the ones I used to encounter back in the north. Which gives me a greater chance in understanding how things work, and how people really think about everything that's going on in Lebanon.
One of the most controversial issues nowadays in Lebanon is Nasrallah's popularity. If you are a Lebanese who used to live here, you'd understand the complexity of the matter. I'll try to illustrate as much as possible, but you have to keep an open-minded mentality and to always remember the diversity of the Lebanese population.
First of all, the south. Up till the end of the last war, the government had no actual presence in the south. Everything was controlled by HA. Being a southerner, you'd feel that HA is the government there, and that if you want to do anything, you need HA authorization. Even ministers and foreign ambassadors couldn't visit cities and villages in the south without HA permission. Not to mention that up till 2000, Israel was occupying a huge part of the south, with all the conflicts of occupation. The majority of southerners are Shiites. And Shiites follow their religious figure (called Imam) almost blindly, or so I have been told. Some even go as far as saying that you are NOT a true Shiite if you disobey your Imam (again, as I have been told by many Shiites friends). HA is like the religious institution that Shiites consider their guardian. Far a Shiite southerner, HA is the one who defend him whenever Israel attacks, HA provide him with security, HA offers him jobs and financial aid to support his family, and lately, HA is the one who would take care of all the houses that were ruined during the war. In short, HA is the "State" where the Shiites feel safe, secure and strong. Taking that into consideration, together with the fact that Shiites solidarity to one another is outstanding and almost 100% perfect, you can fairly say that HA is very very very popular among Shiites, and Nasrallah is considered the "Sole Leader". And when you know that almost 40% of Lebanese population are Shiites, you can have a clear idea about Nasrallah's popularity.
But what about the rest of Lebanon and Lebanese population? I can fairly say that after the last war, all Lebanese (but Shiites) have become against HA. And many of them consider HA as "one (and not the only) causes" of the last war. Ever since PM Rafic Hariri was assassinated, a unique "unity" among Christians, Sunnies and Druze emerged on the surface of Lebanon's daily life. These sects (or at least the majority of them) believe in a true independent STATE of Lebanon, led by a Lebanese government that is the result of the elections. They believe that Taef Record should be applied, and that UN resolutions should be respected, if we want Lebanon to rise from the ashes and prosper as it should have done years ago.
But in Lebanon, politics always divide people, and politicians shift a lot whenever they see an opportunity to gain a higher position. The so called "pro-Syrians" were almost eliminated from the Lebanese political life after Syrian troops withdrawal from Lebanon in April 2005. But now, they saw a "one in a life time chance" to get back on their feet by supporting HA blindly. These people are from all the sects of the Lebanese population. But the major supporter for HA nowadays is the Free Patriotic Movement led by General Aoun. The majority of Lebanese (and I can say that even HA officials) believe that Aoun's presidential hopes are the only reason why he's supporting HA by all means he can afford. Aoun made a huge success in the last elections, specially among Christians voters, which made him claim that he's the "representative" of the Christian community in Lebanon. But lots of those who once believed and supported Aoun in the past (myself included) do not believe in him any more.
In conclusion, it's not a simple issue to know for sure the true popularity of Nasrallah among Lebanese. While many support him to the maximum, others support him for their own benefits. And even those who are against him, some are so because they believe in a country in which the government is the sole decision-maker, and others are so because of their own personal benefit.