William Petroski, and Brianne Pfannenstiel

Des Moines Register

Republicans won control of the Iowa Senate late Tuesday night while ousting Senate Majority Leader Michael Gronstal, a powerful Council Bluffs Democrat who has often been at odds with Republican Gov. Terry Branstad.

Republican defeated at least six Democratic incumbents in the Senate, which gives the party at least 29 seats. No incumbent Republicans in the Senate appeared in danger of defeat. Twenty-six seats are needed in the Senate for a constitutional majority required to pass legislation.

“Serving the people of Council Bluffs and Carter Lake in the Iowa Senate has been the greatest honor of my life," Gronstal said in a statement. "The opportunity to do good, to make a difference in my community, has been incredibly rewarding. I want to thank everyone who has supported me over the years, and all that helped me be successful in the Senate. To you all, I will always be grateful.”

Republicans picked up two seats in the Iowa House, giving them 59-41 edge over Democrats.

The Iowa Legislature's 2017 session, which convenes in January, could mark the first time since 1998 that Republicans have had majorities in both the Senate and House and held the governor's office at the same time. This will give the GOP full control over the state budget and legislative policies and eliminates the possibility that Democrats can block conservative bills.

Senate Republican Leader Bill Dix of Shell Rock issued a statement Tuesday night saying Iowans have clearly stated they are ready to move forward. He praised the newly-elected Senate Republicans, saying they have worked harder than any group of candidates he has ever seen.

"I can promise Iowans that this Republican Senate Majority will implement policies to help create new career opportunities, reduce the size of state government, an improve the quality of life for all Iowans," Dix said.

Gronstal was defeated by Republican Dan Dawson, 38, of Council Bluffs, an Iowa Division of Criminal Investigation agent who is an Army veteran of the wars in Iraq and Afghanistan. The Council Bluffs Nonpareil reported late Tuesday that Gronstal had conceded to Dawson. Gronstal, 66, has been in the Senate since 1985 and earlier served one term in the House. He has been the Senate Democratic leader for the past two decades, serving as both majority and minority leader.

Some Iowa Capitol veterans considered Gronstal to be so influential that he was sometimes jokingly referred to as "Governor Gronstal." Defenders of gay rights and abortion rights viewed him as a hero who repeatedly opposed legislation introduced by social conservatives. Dawson told voters it was time for a change, pledging to work for tax reform, help small businesses, improve education and provide better resources for mental health care

Other incumbent Senate Democrats who lost Tuesday included Chris Brase of Muscatine, Mary Jo Wilhelm of Cresto, Brian Schoenjahn of Arlington, Steve Sodders of State Center, and Tom Courtney of Burlington.

Overall, the new makeup of the Senate includes 29 Republicans, 19 Democrats and one independent. One seat is vacant and will be filled in a special election on Dec. 27.

Andy McGuire, chair of the Iowa Democratic Party, issued a statement expressing disappointment. "We would like to thank all of our Democratic legislators for their years of dedicated service to their districts and constituents. Our Democratic lawmakers will not abandon their priorities in the 2017 legislative session as they renew their fight for adequate education funding, raising the state’s minimum wage and improving our state’s water quality," she said.

Branstad had campaigned statewide on behalf of GOP legislative candidates, seeking support for his policy goals. Republicans have particularly chafed at Democratic control of the Senate under Gronstal, who had become a lightning rod for criticism from conservatives.

With control of both chambers and the governor's office, it's likely that some Republican legislators will push hard to curb state spending and cut corporate taxes, tighten access to abortions and defund Planned Parenthood. Other conservative priorities could include expanding gun rights, weakening public employees' bargaining statutes, and making changes in public employees' pension plans. Most Democratic lawmakers have opposed all of those changes.

Having a GOP majority in both chambers also increases the chances that lawmakers will reach agreement on a funding plan to address Iowa's water quality problems in urban and rural areas. However, the Republican water improvement plan could result in budget cuts in other programs.

Democratic legislators had emphasized support for middle-class families, including an increase in the minimum wage; more state spending on education programs for school districts, community colleges and state universities; and access to health care for all Iowans.

Half of the 50-member Senate was up for re-election Tuesday, while the entire 100-member House was on the ballot.

Dix has been publicly optimistic about his party's chances of winning a majority in the Senate for the past year. He pointed to a half-dozen Senate districts statewide where Democrats held seats, but where Republicans either had an edge in registered voters or were almost even with Democrats. Heading into Election Day, Republicans outspent Democrats in four of the key races, in some cases by more than $100,000.

The party that maintains the most seats in each chamber elects the House speaker and Senate president and appoints committee chairs. But more importantly, the majority party in the House and Senate determines which bills are debated and come up for votes. Under the Iowa Constitution, a bill ordinarily requires 51 votes to pass the House and 26 votes to pass the Senate.

Democrats have held a majority in the Iowa Senate for the past 10 years, although they have had a razor-slim 26-24 edge in seats the past six legislative sessions. In 2005-06, Democrats and Republicans shared control of the Senate with an even 25-25 split. The last time Republicans completely controlled the Senate was in 2004 when they had a 29-21 majority over Democrats. Meanwhile, Republicans have held a majority in the House for the past six years.

New lawmakers will be sworn into their posts in early January when the 2017 session of the Iowa Legislature convenes.

Heading into Tuesday's election, Republicans controlled the House with a 57-43 margin over Democrats. Senate Democrats held 25 seats, while Senate Republicans had 23 seats with one seat vacant, and one seat held by Sen. David Johnson of Ocheyedan, who has switched his status from Republican to independent. The vacant post had been held by the late Sen. Joe Seng, D-Davenport, who died of cancer on Sept. 16.