Obama escalates blitz for Syria attack support NEW: President Obama says his threat to attack is pressuring Syria and its allies Obama does TV interviews Monday before addressing the nation on Tuesday night A new CNN/ORC poll shows most Americans oppose a military attack on Syria Most members of Congress are undecided, but the trend is against Obama Washington (CNN) -- It's a political blitz on Congress perhaps unrivaled in this or other recent administrations -- daily classified briefings, non-stop phone calls, meetings over meals and even a nationally televised speech -- as President Barack Obama's administration tries to convince legislators to authorize a military attack on Syria. The non-stop lobbying intensified Monday with Obama giving one-on-one interviews with CNN and five other television and cable networks, which will be followed by his address to the nation on Tuesday night as well as the plethora of consultations with Congress. All the outreach was intended to reverse a tide of public opposition fueling congressional skepticism over Obama's request for support to launch a military strike on Syria in response to what his administration calls a major chemical weapons attack on August 21 that killed more than 1,400 people. Previously classified video footage first shown publicly on CNN on Saturday showed poison gas victims writhing near death in Syria, providing what the administration hoped would be an emotional exclamation point for its push to attack the regime of President Bashar al-Assad with what are expected to be missile strikes. Obama made sure to mention the images of gassed children in his interview with CNN on Monday, saying the purpose of a military attack would be to prevent similar atrocities as well as the chance al-Assad could use chemical weapons against U.S. allies in the region or American forces. "That's why 98 percent of humanity have said we don't use these" he said. That protects our troops, and it protects children like the ones that we saw in those videos inside of Syria. National Security Adviser Susan Rice later emphasized the human element when she said in a speech that she was unable to look at the images of gassed children "and not think of my two kids." Poll shows public opposition However, a new CNN/ORC International poll showed that concern fueling the public opposition over a Syria attack focuses more on what happens after the missiles hit. According to the survey, eight in 10 Americans believe that the al-Assad regime gassed its own people, but a strong majority doesn't want Congress to pass a resolution authorizing a military strike against it. More than seven in 10 respondents said such a strike would not achieve significant U.S. goals, and a similar amount said it's not in the national interest for the United States to get involved in Syria's civil war, the poll reported. At the same time, the polling showed majority support for an attack that would prevent future use of chemical weapons by Syria or other countries. Republican Rep. Mike Rogers of Michigan, who chairs the House Intelligence Committee and supports a punitive response to Syria's use of chemical weapons, said the classified details his panel has seen make a compelling case. Now the president must do the same to the American people, something he has failed to really try so far, according to Rogers. "He hasn't really talked about Syria in a meaningful way with any depth of understanding of how it impacts the United States at all," Rogers said of Obama on Monday on CNN. He has very poor relations with members of Congress, of both parties, by the way. They are completely disengaged," Rogers continued in reference to the Obama administration. And so they're coming in and asking for a very big thing without allowing I think Americans and most members of Congress who don't sit on national security committees to understand the broader impact of what's going on in Syria. Rogers agreed with the findings of the CNN/ORC poll that the American people and their elected legislators aren't questioning whether banned chemical weapons used. I don't think that's where people's problems are. They are very skeptical about moving forward for a couple reasons," he said. One, they don't understand, nor has it been defined, what is the United States' national security interests? I happen to think they're there, but the president certainly hasn't talked about it at all. That's causing this problem. Administration blitz The administration's blitz began shortly after Britain's Parliament voted on August 29 against joining in any military attack on Syria. Denied a normally reliable NATO ally, Obama shifted his focus to Congress to get political cover for the military strikes he argues are necessary to maintain the credibility of international conventions and treaties against weapons of mass destruction. Since Obama returned from the G20 summit in Russia last week, the lobbying has intensified. His weekly message to the nation focused on the Syria issue, and he joined Vice President Joe Biden for a family style Italian dinner on Sunday night with a handful of prominent Republican senators. Monday brought the president's interviews with the major television networks, while the House and Senate returned from summer recess to begin debating the matter. White House Chief of Staff Denis McDonough met with House Democrats, and Obama himself spent an hour in a meeting that Rice had with generally anti-war Black Congressional Caucus. Later, top officials including Rice, Defense Secretary Chuck Hagel, Joint Chiefs Chairman Gen. Martin Dempsey and Director of National Intelligence James Clapper gave a closed intelligence briefing to House members. On Tuesday, Obama was scheduled to meet separately with Senate Democrats and Republicans before his nationally televised speech in the evening. The president and top officials in the Cabinet and the White House repeatedly emphasize that the attack Obama is contemplating would be limited in scope and duration, with no ground troops involved, to avoid having the situation escalate into another prolonged war like in Iraq. A Senate resolution passed by the Foreign Relations Committee limits any U.S. military response to up to 90 days and specifies no "boots on the ground." "It's not the role of the United States military to go in and inflict regime change through military force because frankly when we do that we're responsible for everything that comes after," Deputy National Security Adviser Ben Rhodes told CNN, adding that "what we're going to do is protect our national security interests and that involves making it clear that nobody in the world should be able to use chemical weapons on the scale that we've seen in Syria and not face consequences." At the same time, he acknowledged the risk of retaliatory attacks by Syria and allies including Iran and Hezbollah in Lebanon that could cause an undesired escalation. "We're prepared for any contingency, of course, and the United States military is far stronger than any of Assad or his allies," Rhodes said, describing an outcome most feared by opponents of a U.S. attack. In his interview with CNN later Monday, Obama downplayed the risk of retaliation by Syria, saying it lacked "a credible means to threaten the United States." Worry about an escalating conflict Opponents question that premise, with veteran GOP Sen. Lamar Alexander of Tennessee announcing Monday he will oppose the resolution authorizing military force "because of too much uncertainty about what comes next." "I see too much risk that the strike will do more harm than good by setting off a chain of consequences that could involve American fighting men and women in another long-term Middle East conflict," Alexander said in a statement. Obama's decision to seek congressional authorization also bought him time to work on getting more support for a unified international response. With news Monday that Russia was proposing that Syria turn over its chemical weapons stockpiles to international control, Obama said the idea could be either a potential breakthrough or an unacceptable stall tactic. He asserted that his threat of a military attack prompted the new Russian offer. "We have not seen these kinds of gestures up until now," Obama said, noting that he discussed the Syria issue last week with Russian President Vladimir Putin at the G20 gathering. The fact that the U.S. administration and I have said we are serious about this, I think has prompted some interesting conversations. The development also prompted a comment from former Secretary of State Hillary Clinton, considered the Democratic frontrunner in the 2016 presidential race if she decides to run, in her first public remarks on the Syrian issue since last month's attack. Clinton said the "inhuman use" of chemical weapons demanded a strong international response "led by the United States," and like Obama, she credited the threat of U.S. military action for what would be "an important step" of Syria's possible surrendering of its chemical stockpiles. In Congress, moderate Democratic Sen. Joe Manchin of West Virginia is proposing an alternative proposal to the attack authorization sought by Obama that would give Syria 45 days to sign on to the global convention banning chemical weapons use. An aide to Manchin said Monday the senator has been promised a vote on the proposal, which is considered a way to avoid an embarrassing defeat for Obama if he can't mount enough support to pass the resolution authorizing military strikes. Meanwhile, Senate Majority Leader Harry Reid was delaying the process of considering the resolution, a Democratic leadership aide said Monday. Reid originally had planned to hold an initial procedural vote on Wednesday, but the aide said the new Russian proposal caused the delay. However, the opposition expressed in polls and CNN's ongoing survey of congressional support showed that the resolution faced an uphill battle to win approval. CNN's Ted Barrett, Dana Bash, Lisa Desjardins and Jamie Crawford contributed to this report.