- President Barack Obama, Hillary Clinton and Donald Trump will be in Michigan soon
- The campaign is focused New Hampshire, Michigan, Pennsylvania and Ohio in the final days, Mook said
"Our strategy these last few days is to focus on the states where voting overwhelmingly happens on election day," Mook told CNN's Alisyn Camerota, pointing to New Hampshire, Michigan, Pennsylvania and Ohio.
"Previously, we've been focused on states like Florida, Nevada, North Carolina where any of the voting happens early. So this is really a reflection of the voting calendar," he added.
But Mook said
Saturday that the campaign is taking tightening polls in the Midwest "seriously."
Clinton will campaign in Grand Rapids, while President Barack Obama will rally supporters
in Ann Arbor on Monday, as a recently released Detroit Free Press poll found that Clinton is up 4 percentage points in Michigan, 42% to Trump's 38%.
The Republican presidential nominee is also spending time in Michigan Monday, where he is set to hold a late-night rally in Grand Rapids.
Trump's campaign manager Kellyanne Conway predicted Monday that Trump will win Michigan, and told, "Good Morning America" that that campaign feels "really good" about the latest polling in upper Midwest states.
On Monday Clinton is set to campaign in Pennsylvania, Michigan and North Carolina, while vice presidential nominee Tim Kaine will hold events in North Carolina and Virginia.
Vermont Sen. Bernie Sanders will rally supporters in Las Vegas Monday afternoon and Al Gore will campaign in Colorado, where the latest polls
show that the Democratic nominee is running neck-and-neck with Trump.