With less than four weeks until primary ballots go out to Colorado voters, Democratic U.S. Senate candidates John Hickenlooper and Andrew Romanoff are planning to take part in an online forum Thursday night, organizers said.

The forum, sponsored by the progressive IndivisibleNOCO group, will mark the first time the two candidates have met since the primary ballot was finalized late last week.

The winner of the June 30 primary will face Republican U.S. Sen. Cory Gardner in a contest that could determine which party controls the U.S. Senate after the November election.

“We want to make sure that our next senator is up to the task of representing Colorado and willing to take on issues that are important to progressive constituents,” organizers said in a Facebook post announcing the event.

The forum will be moderated by Gordon McLaughlin, a deputy district attorney and the Democratic nominee for DA in Larimer and Jackson counties’ 8th Judicial District.

Organizers said the candidates will be asked to discuss topics including health care, climate change, immigration, campaign finance reform and the response to the coronavirus pandemic.

The forum will take place 7-9 p.m. on the Zoom platform, and pre-registration at this link is required. Participants are asked to join the forum no later than 6:55 p.m.

Hickenlooper, a former two-term governor, qualified for the primary by petition. Romanoff, a former speaker of the state House, was the only candidate to emerge from the Democrats’ caucus and assembly process.

Primary ballots start going in the mail to voters on June 9.