At age 16, he moved to New Hampshire, and worked as an apprentice for three years in the print shop of John Randall Reding.

After leaving Dartmouth, he studied law in Boston in the office of Robert Rantoul, Jr., and was admitted to the Massachusetts bar in 1845.

Rather than retiring, Doty chose to run as an Independent Democrat in the election and easily defeated Hobart.

[2] Hobart was then the Democratic candidate for Governor of Wisconsin in the 1859 election, but was defeated by incumbent Republican Alexander Randall.

Hobart enlisted two weeks after the outbreak of the American Civil War and helped raise a company of volunteers for the Union Army from the Chilton area.

The regiment left Wisconsin in September 1862, but Hobart would not rendezvous with them until a month later due to travel time from Louisiana.

Before Hobart's arrival, the 21st had marched to join the Army of Ohio, which had been carrying out a defense against the Confederate Heartland Offensive in Kentucky.

The 21st was now organized under Major General William Rosecrans' Army of the Cumberland, engaged in a counter-offensive against Confederate forces in Tennessee.

With Colonel Sweet incapacitated, Hobart took command of the regiment and lead them at the battles of Stones River and Hoover's Gap.

[5] General Lovell Rousseau, in his report on the battle of Stones River, mentioned Hobart and the 21st for their good conduct.

After the Union successes in central Tennessee, the 21st advanced toward Chattanooga with the Army of the Cumberland, eventually pushing into Georgia.

Hobart ordered the regiment to retreat to the second line of defenses, where they continued to hold until nearly surrounded by Confederate forces.

The regiment marched from Lookout Mountain on May 2 to join the Atlanta Campaign, attached to General William Tecumseh Sherman's army.

At the Battle of Rocky Face Ridge, the 21st joined in the flanking maneuver that forced the Confederates to abandon their position and fall back toward Resaca.

The regiment received severe bombardment during the Battle of Kennesaw Mountain, but held their ground until Sherman's flanking maneuver forced the enemy to abandon their position.

Though they did not see significant fighting, they participated in the burning of Marietta, Georgia, and foraged for food and supplies to provision the army during its march.

Hobart's brigade reached Goldsboro, North Carolina, on March 23, and was the first unit to enter Raleigh, on April 13.