Obama leads Romney 49 percent to 44. Obama led the same poll 47 to 46 percent in late July.

Independent voters are predominantly responsible for the Wolverine State’s swing toward Obama. Romney led by 10 among independents in July, but Obama has grabbed a 6-point lead with the group in the August survey.

Mitchell Research Chairman Steve Mitchell said Romney’s selection of Rep. Paul RyanPaul Davis RyanMcConnell names Senate GOP tax conferees House Republican: 'I worry about both sides' of the aisle on DACA Overnight Health Care: 3.6M signed up for ObamaCare in first month | Ryan pledges 'entitlement reform' next year | Dems push for more money to fight opioids MORE (R-Wis.) hasn’t had any impact on the race in Michigan.

“Just two days after being named to the ticket as Romney’s vice presidential pick, Wisconsin Congressman Paul Ryan doesn’t seem to have had any impact on the race,” he wrote. “When his name and Vice President Joe BidenJoseph (Joe) Robinette BidenOvernight Tech: FCC won't delay net neutrality vote | Google pulls YouTube from Amazon devices | Biden scolds social media firms over transparency Medicaid funds shouldn't be used to subsidize state taxes on health care Biden hits social media firms over lack of transparency MORE’s name are added to the trial ballot question, it remains exactly the same, 49 to 44. Two days is too short of a time period to determine what the impact of Ryan’s candidacy will mean to the ticket.”

Obama once had a commanding lead over Romney in Michigan, up by double digits as recently as mid-May, according to the Real Clear Politics average of polls. The race tightened after Romney became the presumptive Republican nominee, but Obama has since pulled away, leading by 7.7, according to the RCP average.

Romney’s father, George Romney, was once governor of Michigan, and Romney spent his childhood there. Still, many didn’t believe the former Massachusetts governor would devote significant resources to a state that until recently looked to be out of reach.

 Michigan has swung reliably Democratic in recent years.

Obama won it by 16 points in 2008, and Romney barely won the state’s Republican primary earlier this year. Romney edged Rick Santorum by 3 percent in the primary, but effectively split the delegate count with him; at the time, many called it a blown opportunity for the former Pennsylvania senator, who got wrapped up in controversial social issues just prior to the primary. 

Michigan is one of 12 swing states that will be critical in determining the outcome of the 2012 election.

The poll of 1,079 likely voters was conducted on Aug. 13 and has a 3 percent margin of error.