(CNN) - President Barack Obama's approval rating may be struggling, but he's still bringing in money on the fundraising trail.
For the past month, the President has been crisscrossing the country raising cash for Democratic campaign groups. At 13 separate events in eight cities, he may have helped raise up to $21.6 million.
In his latest West Coast, three-day circuit that he capped off Tuesday night, Obama helped bring in up to $12.8 million, alone.
All calculations are based off estimated guest counts and ticket price ranges from various Democratic officials. The figures represent the maximum amount he could have possibly raised, so the total sum could be much less.
At the beginning of the year, Obama pledged to attend 14 fundraising events for Congressional Democrats in 2013. Running his own campaign last year, the President didn't have much time to stump for his colleagues on Capitol Hill.
His fundraising swings benefit three groups: the Democratic National Committee, the Democratic Congressional Campaign Committee and Democratic Senatorial Campaign Committee.
While he's been attending events all year, the past month marked perhaps his most robust blitz. Since October 25, Obama stopped for cash in New York, Massachusetts, Texas, Florida, Pennsylvania, Washington state, and California.
The President hobnobbed with several high profile figures, including NBA legend Earvin "Magic" Johnson, Tom Hanks, Rita Wilson, Samuel L. Jackson, and Obama bundler and film producer Harvey Weinstein.
It's no secret some people will pay big money to wine and dine with the President. Tickets at the various events ranged from $2,500 to the maximum allowed amount of $32,400.
One reason for the last month's frenetic pace has to do with a pause in fundraising during September and part of October, as Washington grappled with the crisis in Syria and the government shutdown. Obama, for example, was originally scheduled to attend at least one of the California fundraisers in September, but he had to postpone to make his case before Congress for military action in Syria.
His administration has also been busy dealing with the botched launch of HealthCare.gov. The President acknowledged earlier this month that the rocky rollout of Obamacare may hurt Democrats in the voting booth next year.
"There is no doubt that our failure to rollout the ACA smoothly has put a burden on Democrats, whether they are running or not because they stood up and supported this effort through thick and thin," Obama said.
Speaking to donors in Seattle this week, Obama tried to drum to a more optimist beat, saying Americans have always been able to overcome obstacles.
"As long as there were those who stayed steady and clear-eyed and persistent, eventually we came up with an answer," he continued. "Eventually we were able to work through these challenges and come out better on the other end."
Democrats need to pick up 17 seats next November in the House in order to gain control of the chamber. The Senate is defending its 55-45 majority.
- CNN Political Editor Paul Steinhauser contributed to this report.