BISMARCK, N.D. — North Dakota Democrats are preparing for an annual convention featuring speeches from Sen. Heidi Heitkamp and former Vice President Joe Biden as they look to build enthusiasm for a midterm election expected to be favorable for their party nationwide.

But as the party gathers in Grand Forks, its outlook at home is challenging.

Heitkamp faces a tough re-election fight against Rep. Kevin Cramer in one of the nation’s mostly closely watched Senate races. Three Democrats are trying for the House seat Cramer is leaving.

But the party has no declared candidates for attorney general and agriculture commissioner — positions that make up two-thirds of a panel that oversees energy development in the state. Democrats are also still searching for many legislative candidates as they try to chip away at Republican supermajorities in both chambers.

The convention starts Thursday at the Alerus Center, with most key business — including the Heitkamp and Biden speeches and an endorsement in the House race — happening Saturday.

Party Chairwoman Kylie Oversen, said she expects all candidate spots to be filled. She said Heitkamp’s past success in the conservative state has bolstered enthusiasm among delegates and office-seekers.

More than 625 delegates are expected to attend, which would be higher than the Democrats’ three previous conventions, said Daniel Tick, a state party spokesman.

Republicans have controlled both chambers of the Legislature since 1994 and have the most lopsided advantage in recent history. In the Senate, the GOP has a 38-9 edge; in the House, it’s 81-13.

Democrats as of Wednesday had no declared House candidates in about a dozen districts. Each district has a senator and two representatives.

“I think we will pick up (legislative) seats in North Dakota and potentially one or two statewide seats,” said Oversen, who herself is running against Tax Commissioner Ryan Rauschenberger, a Republican.

“We have a lot of really strong candidates and having Sen. Heitkamp on the ballot is helpful for them,” Oversen said. It also will be helpful for Heitkamp, she said.

“She has broad-based support and we expect that to be visible at the convention,” she said.

The U.S. House seat left open by Cramer’s Senate bid has attracted strong interest from both parties. Jamestown state Sen. John Grabinger and former state lawmakers Mac Schneider of Grand Forks and Ben Hanson of Fargo are seeking the Democratic endorsement at the convention.

For Republicans, former U.S. Marine Tiffany Abentroth and state Sens. Kelly Armstrong and Tom Campbell are seeking endorsement next month at the party’s convention that also is being held in Grand Forks.

Convention endorsements give a favored candidate a guaranteed spot on the June 12 primary ballot and party support for a campaign. They don’t prevent primary challenges, though each of the Democratic hopefuls says they will drop out if not endorsed.

Democrats don’t yet have opponents for Attorney General Wayne Stenehjem and Agriculture Commissioner Doug Goehring. Stenehjem is a former Grand Forks state senator who was first elected attorney general in 2000 and Goehring is seeking his third term. Along with Gov. Doug Burgum, they make up the Industrial Commission, which oversees everything from energy production to the state-owned Bank of North Dakota.

Democrats are still searching for a second candidate to run against GOP Public Service Commissioners Randy Christmann and Brian Kroshus. Casey Buchmann, of Washburn, is seeking the Democratic endorsement for the seat now held by Kroshus.

The three-member panel regulates coal mining, land reclamation, pipelines, electric and gas utilities, grain elevators, telecommunications and auctioneers. A big part of its recent workload has involved determining locations for oil and natural gas pipelines, natural gas processing factories, and wind energy projects.

Fargo Rep. Josh Boschee is seeking the Democratic endorsement for secretary of state against GOP incumbent Al Jaeger, who has served more than two decades in the office that is best known for supervising elections.

Jaeger is being challenged within the GOP by Mandan businessman Will Gardner.