Wisconsin Rep. Mike Gallagher (R) raised nearly $625,000 in the second quarter amid speculation he could run for Senate in 2022, according to numbers first released to The Hill on Monday. 

Gallagher's campaign told The Hill his campaign raised $304,000 and his joint fundraising committee raised $315,000 during the period. 

The congressman's latest haul follows his first-quarter fundraising haul of $830,000, bringing his six-month fundraising total to nearly $1.5 million. Gallagher has $2.3 million on hand, according to his campaign. 

While the congressman's 8th Congressional District is considered safely Republican, he has been floated as a potential Senate contender if Sen. Ron Johnson (R-Wis.) decides not to run for reelection in 2022. Johnson has not yet made an announcement on whether he will run again. 

In addition to Gallagher, former Rep. Sean Duffy (Wis.) and former Lt. Gov. Rebecca Kleefisch have been floated as possible Republican contenders. 

Several Democrats have filed to run in the race, including state Sen. Chris Larson (D), State Treasurer Sarah Godlewski, Outagamie County Executive Tom Nelson, Milwaukee Bucks executive Alex Lasry, radiologist Gillian Battino, businessman Adam Murphy and attorney Peter Peckarsky. 

Wisconsin stands to be a consequential state in the battle for control of the upper chamber next year. President Biden narrowly won the state against then-President Trump in 2020 after Trump flipped it in 2016.

The Cook Political Report rates the seat as "lean Republican."