Competitive primaries happened yesterday in several of the Iowa Senate districts that will determine control of the upper chamber for the next two years. Full results are on this page of the Secretary of State’s website.

My first take on the general election match-ups is below. I still see Democrats favored to hold their majority, with a decent chance of expanding it.

Democrats appear to be in a strong position to hold their Iowa Senate majority, based on a first review of the landscape since the filing period for major-party candidates ended yesterday.  

Democratic State Senator Dennis Black announced this morning that he is retiring from politics after 32 years in the Iowa legislature, including five terms in the Iowa Senate. His retirement opens up Senate district 15, covering most of Jasper County and parts of eastern Polk County. As of March 2014, this district contained 15,238 registered Democrats, 13,184 Republicans, and 15,064 no-party voters. After the jump I’ve posted a district map and Black’s open letter to colleagues and the media.

In late January, it appeared that three Republicans would compete for the chance to run against Black this year. But the highest-profile candidate, former Iowa GOP Co-Chair David Fischer, opted against running last month. Meanwhile, the first Republican candidate to declare against Black, Patrick Payton, decided to run for Iowa House district 29 instead. That leaves Crystal Bruntz, a human resources executive for the convenience store chain Kum & Go, as the likely GOP nominee in Senate district 15. So far she is the only Republican who has filed nominating papers in the district.

Democrats have until this Friday to find a new candidate for the seat Black is vacating. I am seeking comment from two-term State Representative Dan Kelley of Newton. He currently represents Iowa House district 29 but has not filed for re-election yet. First-term Democrat Joe Riding has already filed for re-election in House district 30, the western half of Senate district 15. UPDATE: Riding confirmed by telephone that he is committed to continuing to represent residents of House district 30.

Although Black’s district wasn’t initially on my radar or Senate Majority Leader Mike Gronstal’s radar as one of the most competitive 2014 Senate races, opposing parties typically have a better chance of winning open seats than defeating state legislative incumbents. Senate district 15 will surely be a race to watch this year.

PROCESS GEEK UPDATE: Although it’s not relevant in this instance, since Riding will stick with the House race, a candidate who had already filed papers to run for an Iowa House district could file for a newly open Senate district. Scroll to the end of this post for the explanation.  

Iowa Senate Majority Leader Mike Gronstal is “fairly confident” going into this year’s state legislative elections, he told Mike Glover in a recent interview. He cited a “pretty good message” to take to voters as well as a “a slight advantage on the map” that will allow Democrats to play “a little less defense and a little more offense,” compared to 2012.

I agree with Gronstal that Democrats are better positioned now to hold their 26 to 24 majority in the upper chamber than they were at the same point two years ago. Follow me after the jump for a quick look at the eight districts the Senate majority leader expects to be targeted this fall.

It’s the time of year for blog posts about notable candidates and upcoming elections. Every politically engaged Iowan knows already that 2014 will be an unusually exciting year. We haven’t seen an open U.S. Senate race since 1974. The last time Iowa’s first Congressional district was open was in 2006. The last time Iowa’s third Congressional district was open was in 2002, but it wasn’t a wide open seat, since incumbent Representative Leonard Boswell moved into Polk County to run. Amazingly, 1940 was the “last time there was a Congressional race in Polk County without an incumbent seeking re-election.” All of Iowa’s statewide elected officials are up for re-election as well this year, and the secretary of state’s position may become open if Matt Schultz decides to go for the Republican nomination in IA-03.

Since Bleeding Heartland readers already know about the big Iowa races to watch, I want to focus today and tomorrow on the elections that are likely to determine control of the Iowa House and Senate in 2015 and 2016.  

The Daily Kos Elections team has been compiling 2012 presidential election results by state legislative district as well as by Congressional district. Yesterday the Iowa numbers were added to the database. You can view Google documents with raw vote totals and percentages for Barack Obama and Mitt Romney by Iowa Congressional district here, by Iowa Senate district here, and by Iowa House district here.

Looking closely at the presidential vote in the legislative districts provides some insight about where the competitive Iowa statehouse races might be next year. After the jump I’ve highlighted some key data points related to the Iowa Senate races. Later I will post a separate diary with first thoughts about the Iowa House districts.